Gluten Free Zucchini Parmesan Squares

Gluten Free Zucchini Parmesan Squares

Make good use of that abundant summer squash in this easy recipe for savory gluten free zucchini parmesan squares. Perfect for a picnic lunch or a snack!

Make good use of that abundant summer squash in this easy recipe for savory gluten free zucchini parmesan squares. Perfect for a picnic lunch or a snack!

A great summertime snack (really!)

I have two teenage girls, and they both play softball competitively. That means lots (and lots) of packed coolers, and when you’re playing in the summertime heat, you need the good snacks that are easy to eat and don’t weigh you down.

On every team, there’s that mom that you might think I would be (but you would be wrong, sadly): lots of homemade food cut into the perfect size to eat on the go, packed perfectly and served at just the right moment. I do, however, bring all the right chips, lots of fruit, and homemade chocolate chip cookies to share.

The first time I learned of these zucchini parmesan squares, I was sitting beside that mom on one of my daughter’s softball teams. She isn’t gluten free, so I didn’t try the squares even though she was so generous in offering them to everyone.

She said that she makes these squares every summer and that they’re flavorful, packed with vegetables (thank you, summer squash!). When she said that the squares are at their best when served at room temperature, I knew I had to try to make a gluten free version.

She started to describe the recipe, and it sounded a lot like a version of our 1970’s special spinach balls. Every other person there tried it (even the youngest siblings, who had no idea they were eating vegetables).

Make good use of that abundant summer squash in this easy recipe for savory gluten free zucchini parmesan squares. Perfect for a picnic lunch or a snack!

How to make zucchini parmesan squares

To make the squares, whisk together the flours, leaveners, salt, herbs, spices, and grated cheese. Then add the nearly 2 cups of grated zucchini to a large bowl and toss it to separate the grated vegetable pieces.

In a separate bowl or larger measuring cup, whisk together the eggs, oil, sour cream, and grated onion, then add that wet mixture to the large bowl of dry ingredients. Mix to combine, and transfer to a greased baking pan. Sprinkle the top with some more cheese (grated or shredded Parmigiano-Reggiano), and bake for about 30 minutes.

Make good use of that abundant summer squash in this easy recipe for savory gluten free zucchini parmesan squares. Perfect for a picnic lunch or a snack!

How to make it even easier

If you glanced at the ingredient list in the recipe below and got intimidated because it’s kind of a long list, stop ✋🏻right there. I promise the list is only lengthy because of the dried spices (which are completely ordinary and are definitely already in your pantry). 

Plus, instead of using a ready-made pancake mix, I broke down the flour-baking powder-baking soda-salt. Since the original recipe calls for using Bisquick, I began by using our homemade gluten free pancake mix (since I always have some of that on hand). I found that the recipe turned out just as well and was even simpler to make when I used an all purpose gluten free flour blend.

Since zucchini has such a mild taste, and this recipe is made with oil instead of butter which is naturally more flavorful especially in baking, you really do need to use plenty of spices. Garlic powder instead of minced fresh garlic added more depth of flavor to the squares. You can actually replace the grated onion with 2 tablespoons of dried minced onion and 1/2 teaspoon onion powder.

Make good use of that abundant summer squash in this easy recipe for savory gluten free zucchini parmesan squares. Perfect for a picnic lunch or a snack!

Ingredients and substitutions

Dairy-free: The dairy in this recipe comes mainly from the Parmigiano-Reggiano cheese. It’s a tough one to replace, but not impossible. I recommend replacing it with 1/4 cup nutritional yeast (for that cheesy flavor) and the remaining amount as shredded nondairy cheese.

I like Violife brand or Daiya, but if you can find Violife brand, they have a Parmesan alternative that looks promising for the whole amount.  The sour cream can easily be replaced with an equal amount of plain nondairy yogurt. My favorite nondairy plain yogurt is by So Delicious brand. 

Egg-free: There are 5 whole eggs in this recipe. I’m afraid that’s just too many eggs to expect to replace them successfully with an egg replacer like a chia egg or a flax egg (even if you boil the flax seeds and strain them out). So sorry!

Corn-free: This one’s super easy. The cornstarch is there to lighten up our standard all purpose gluten free flour blend. In its place, you can use potato starch or arrowroot in an equal amount. 

Oil: The original recipe calls for vegetable oil, but I found the recipe to be too bland (and frankly, oily tasting) that way. So I switched to extra virgin olive oil, and it made a big difference. You could probably also use melted butter, and it would be delicious. 


Make good use of that abundant summer squash in this easy recipe for savory gluten free zucchini parmesan squares. Perfect for a picnic lunch or a snack! #glutenfree #snack #zucchini #summer #gf

Like this recipe?

Prep time: Cook time: Yield: About 10 servings


1 cup + 1 tablespoon (149 g) all purpose gluten free flour (I used Better Batter)

1/2 teaspoon xanthan gum (omit if your blend already contains it)

2 tablespoons (18 g) cornstarch

1 teaspoon baking powder

1/8 teaspoon baking soda

1 1/4 teaspoons kosher salt

1 tablespoon dried parsley

1/2 teaspoon dried oregano

1 1/2 teaspoons garlic powder

3/4 cup (75 g) finely grated Parmigiano Reggiano cheese, plus more (shredded or grated) for sprinkling

Heaping 3 1/3 cups (375 g) grated raw zucchini

5 eggs (250 g, weighed out of shell), at room temperature

1/2 cup + 2 tablespoons (140 g) extra virgin olive oil

2 tablespoons (30 g) sour cream, at room temperature

1 small yellow onion, peeled and grated

Fresh flat leaf parsley, chopped (optional, for serving)


  • Preheat your oven to 350°F. Grease the bottom and sides of a 13-inch x 9-inch x 2-inch baking pan. Set it aside.

  • In a large bowl, place the flour, xanthan gum, cornstarch, baking powder, baking soda, salt, parsley, oregano, garlic powder, and 3/4 cup cheese, and whisk to combine. Add the grated zucchini, and mix to combine and evenly distribute the zucchini throughout the dry ingredients. In a separate small bowl or 1 quart or larger measuring cup, place the eggs, oil, sour cream, and grated onion, and whisk to combine well.

  • Create a well in the center of the dry ingredients in the large bowl, pour in the egg and oil mixture, and mix to combine. The mixture will be thick but soft. Transfer it to the prepared pan and spread into an even layer. Sprinkle the top evenly with the remaining grated or shredded cheese.

  • Place the pan in the center of the preheated oven and bake until puffed and lightly golden brown (about 30 minutes). Allow the casserole to cool for at least 10 minutes in the baking pan before cutting it into 2-inch squares. Sprinkle with the optional chopped fresh parsley, and serve warm or at room temperature. Store any leftovers in a sealed container in the refrigerator.

  • Adapted from Betty Crocker (hat tip to the mom on my daughter’s softball team for the idea!)


Comments are closed.

  • Nancy
    July 18, 2019 at 4:57 PM

    I’m excited to make these tonight! I think the recipe’s “gram” measurement of the grated zucchini might be a bit high? Or I’m measuring it incorrectly on my scale…

    • Nicole Hunn
      July 18, 2019 at 6:02 PM

      There’s no error in the recipe, Nancy. Just ignore the volume measurement and go by weight. Weight measurements are significantly more accurate, which is why they’re preferable!

  • Shelaine
    July 8, 2019 at 12:15 PM

    Mine is in the oven right now for a summer dinner on the side of some grilled salmon and a salad! In the UK, and using doves brand of gf flour so will update for those who are here. Subbed grano padona for the parmesan because for some reason ive always preferred it and find it subs well

    • Nicole Hunn
      July 8, 2019 at 12:43 PM

      Oh my gosh, Shelaine, that sounds like the perfect summertime dinner! I’m hopeful that Dove’s worked well. Thanks for letting us know about your preferred cheese.

  • Maggie C.
    July 7, 2019 at 1:20 PM

    – [x] Hi Nicole! I found your website a few months ago and purchased your book GFOAS Bakes Bread. Your recipes have helped bunches. Thanks for all of your hard work in putting this all of the recipes together! I’m currently trying to recreate Cardamom bread (Pulla bread) that my mom and I used to make for the holidays before I was diagnosed with Celiac disease a little over 3 years ago. The recipe we used to use seems similar to your Challah bread recipe, but only uses 1 egg and heating milk, sugar, and butter before adding it to the flour mixture. We’ve tried making the old recipe using Bob’s Red Mill and Cup4Cup one-to-one flour replacement (this was before I found your website/books), but the dough hasn’t risen. Have you had any experience making this type of bread GF or any suggestions for helping me recreate it? Do you think I should try making it with the old recipe, but with your bread flour blend or just adding the cardamom spice to your Challah bread recipe? Again, thanks bringing baking bread back into my life!

    • Nicole Hunn
      July 7, 2019 at 4:10 PM

      Hi, Maggie,
      Gluten free recipes really are different, and I’m afraid there is no such thing as a true GF cup for cup replacement for conventional flour (see this explanation here). But you can try using my bread flour blend from GFOAS Bakes Bread. It may also require more moisture, but I’m afraid that’s all I can really guess at!

  • Kelly
    July 7, 2019 at 11:05 AM

    The description says almost 4 cups, but the recipe states 1 3/4 cups of zucchini. Is it supposed to be 3 3/4 C?
    Thanks for the clarification!

    • Nicole Hunn
      July 7, 2019 at 4:14 PM

      Hi, Kelly, yes, the recipe is correct as written. The reference to “nearly 4 cups” in the description is a typo, and should say (and now does say) “nearly 2 cups.” So sorry for the confusion!

  • Lisa L
    July 7, 2019 at 10:05 AM

    Hi Nicole—Quick question: The “How to Make…” section says to add nearly four cups of grated zucchini but the recipe directions list 1 and 3/4 cups of zucchini. Which is it? Or does the amount of zucchini even matter?

    • Nicole Hunn
      July 7, 2019 at 4:14 PM

      Hi, Lisa, yes the amount always matters! The amount in the description in the body of the post was a typo (which I have no fixed so it correctly reads “nearly 2 cups”). The recipe is correct as written! So sorry for the confusion.

  • Kathy
    July 7, 2019 at 9:56 AM

    I have a question about the amount of zucchini-there’s one place that says nearly 4 cups, but in the recipe it has 1 3/4 cups. Is the amount in the recipe correct? I’m looking forward to trying this, it looks really good!

    • Nicole Hunn
      July 7, 2019 at 4:13 PM

      Yes, thank you for pointing that out Kathy, the recipe is correct as written. The reference to “nearly 4 cups” in the description is a typo, and should say (and now does say) “nearly 2 cups.” So sorry for the confusion!

  • Julie L
    July 7, 2019 at 9:42 AM

    Okay Nicole, thanks for the tip! One year I tried shredding and dehydrating some of the gigantic zucchini I’d been “gifted” and it was a failure- it wouldn’t rehydrate. But I do have a chest freezer now so I’ll give that a go (probably with some regular sized though 😁).

    • Nicole Hunn
      July 7, 2019 at 4:13 PM

      Be wary of really large zucchini, Julie. They are nearly all water. I’m afraid when they get that large, they’re basically no longer useful at all.

  • Michelle
    July 7, 2019 at 9:15 AM

    This looks delicious! Is it necessary to squeeze out the zucchini ? I know I’ve done that for other recipes .

    • Nicole Hunn
      July 7, 2019 at 4:12 PM

      Hi, Michelle, Nope! You use the grated zucchini as is. If I ever expect you to wring out the moisture, I am sure to specify that in the recipe!

  • Cindy
    July 7, 2019 at 7:58 AM

    To drain or not to drain the zucchini? I’ve always wrung mine out in a dishcloth. Thoughts?

    • Nicole Hunn
      July 7, 2019 at 8:05 AM

      Hi, Cindy, in many of my zucchini recipes, I do wring it out (and of course specify that in the instructions). In this recipe, you don’t wring it out. The extra moisture is part of the recipe, actually! And it’s not an especially delicate recipe that will suffer from the variable moisture in different zucchini. I hope that’s helpful!

  • Shauna
    July 6, 2019 at 2:57 PM

    Thanks this will really help

  • Kathy
    July 6, 2019 at 1:39 PM

    Going to try this my husband is lactose and glutin free. Very difficult sometimes with recipes for sweets and dinners. Thanks for the recipe. Sure looked good to me

  • Vicki
    July 5, 2019 at 8:35 PM

    Looks great but I need to know nutrition information. Especially need to know the amount of carbs, protein, fiber and sodium. It is way too much work for me to figure this out for every recipe so it would be really appreciated if it would be there so I can decide whether to make a recipe or not.

    • Nicole Hunn
      July 6, 2019 at 3:05 PM

      Hi, Vicki, At this time, I’m afraid I don’t have nutrition information to provide for any recipes that I don’t label as “low carb” or something similar. I’m afraid I simply don’t have the time to calculate nutrition information for all of my recipes, but feel free to use an online nutrition calculator!

  • Cheri L.
    July 5, 2019 at 6:23 PM

    She addresses the pancake mix in her comment section. If you have some gluten free pancake mix ready made like I do, then substitute it for the flour , baking soda, baking powder, salt, xanthan gum and cornstarch. Adjust the total amount of pancake mix to include all 6 ingredients. If not, if you don’t have any premade, she says it’s just as easy to use better batter and to add in the baking soda ,baking powder, salt, xanthan gum and cornstarch to the recipe. I suspect it depends on what you already have which one is easier. In the final analysis the ingredients are pretty much the same. Gluten free pancake mix usually has added sugar.

    • Nicole Hunn
      July 6, 2019 at 3:04 PM

      Thank you for jumping in, Cheri. And yes, I like being able to eliminate the sugar that is in premade pancake mix here!

  • GFMum
    July 5, 2019 at 5:56 PM

    I’m trying to rate this, but nothing happens when I click on it…

    • Nicole Hunn
      July 6, 2019 at 3:32 PM

      Thanks for pointing that out, GFMum. I checked, and I’m having the same experience. I will ask my web developer about it right away! Thanks again.

  • GF Mum
    July 5, 2019 at 5:52 PM

    Hi Nicole! I made this for dinner tonight… Delicious! Had some gruyère in the fridge, so I sprinkled a little on top. Yum! Thank you!

    • Nicole Hunn
      July 6, 2019 at 3:03 PM

      That sounds perfect!!

  • Julie L
    July 5, 2019 at 3:59 PM

    Our weekends revolve around easy grab and munch meals, and this looks wonderful. Do you think I could easily substitute a different vegetable that I might have on hand like roasted cauliflower or sauteed asparagus? Summer squash goes quickly and I don’t always have it on hand, but if it’s necessary for structure I could hide it until I’m ready to use it ;)
    Thanks Nicole!

    • Nicole Hunn
      July 6, 2019 at 3:03 PM

      Hi, Julie,
      I’ve actually thought quite a bit about what else, other than summer squash, you could use in this recipe, and I haven’t come up with anything I feel comfortable recommending without lots of extra recipe testing. I don’t think that asparagus would work at all, I’m afraid, or cauliflower. I had wondered about mushrooms, actually, but I’m still kind of doubtful. If you’re concerned about not having squash on hand, I recommend buying a ton when it’s in season, shredding it all, and freezing it in portions. Then, defrost it at room temperature and use it in the recipe. I do it all the time!

  • Vivian Howard
    July 5, 2019 at 3:01 PM

    How about using Gluten Free Bisquick Pancake and Baking Mix, to simplify things and get back close to the original recipe.

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