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No need for a mix for these extra tender gluten free sugar cookie bars made with sour cream. Instead of frosting, the vanilla sugar on top creates an ultra-thin crackling crust.
These sugar cookie bars aren't just basic sugar cookies in bar form. Not that I'm throwing shade; I love basic sugar cookies.
From drop cookies to cutout cookies, vanilla to chocolate to maple-flavored, I adore them all. But these bars just aren't essentially the same type of recipe but baked in a pan and sliced into bars.
They're softer and more tender, with a mild tang from all that sour cream baked into the cookie dough. They aren't burdened by the need to hold a shape and clean lines, so they devote themselves fully to flavor.
How to make vanilla sugar
Sugar cookie bars are often served with a thick layer of buttercream frosting. I guess the inspiration is the Lofthouse-style cutout sugar cookies that have that gorgeous thick layer of frosting.
But this gluten free sugar cookie bars recipe is more delicate in texture. Along with the extra tender cookie bar, they have a razor-thin layer of vanilla sugar on top that bakes into a satisfying crackle topping.
To make vanilla sugar, place granulated sugar and as many vanilla bean seeds as you're willing to spare in a food processor. Pulse a few times.
I use the seeds from 1/2 of a vanilla bean for each 1/2 cup of granulated sugar. That's a relatively generous amount, so feel free to use fewer seeds since vanilla is just. so. expensive.
The mixture will clump, but it will still keep for a long time at room temperature. I store it in a sealed glass jar and press it with a spoon to break up clumps before using it.
Be sure to keep it in a glass container, not plastic. Plastic will absorb the aroma rather than preserve it in the sugar. And keep the jar covered, to keep that lovely smell contained.
Make these sugar cookie bars thinner or thicker
I've made these tender, flavorful cookie bars both about 1-inch thick, and about 1/2-inch thick. I prefer them thicker, but I've provided instructions for how to do either.
Regardless of thickness, doneness can't be determined visually or with your hands. You can't press gently in the center of the pan without cracking the thin sugar crust. And you can't see underneath the crust to determine if it's set in the center.
Thicker bars
In the photos here, the bars are nice and thick, with a generous crackly vanilla sugar crust. If you'd like them thick like that, just make them in a 9-inch square pan.
The baking time is about 30 minutes, or until a toothpick inserted in the center comes out clean.
Thinner bars
To make thinner bars, you'll need a 9-inch x 13-inch x 2-inch pan. The baking time is about 22 minutes.
You can't use a jelly roll pan, with sides that are less than 2-inches, because it doesn't have enough volume. You'll need something with higher sides.
Be sure your oven temperature is no higher than 350°F as indicated by a separate thermometer. A higher temperature will burn the underside in the center before the rest of the cookie dough has finished baking.
For cutout cookies
If you're looking for cutout cookies that you can make into fancy shapes, I have plenty of other recipes for that. Have a look at our recipe for soft gluten free cutout sugar cookies.
For a tangier version that is more similar in taste to these sour cream sugar cookie bars, try our recipe for gluten free cream cheese cutout sugar cookies. For the tenderness and taste of the cookie alone, that recipe can't be beat if you're in need of a shaped cookie.
Ingredients and substitution
Dairy
In place of the butter in this recipe, try using vegan butter. My favorite brands are Melt and Miyoko's Kitchen.
In place of the sour cream, you can use plain Greek yogurt (dairy or nondairy). You cannot use plain yogurt of any kind that is the “regular” thickness, since that has too much moisture.
If you use an ingredient like plain “regular” yogurt with too much moisture in it, the recipe won't work—and you can't say I didn't warn you! Plus, I will continue to push back on comments that blame me for errors that were not recipe-related, but execution-related.
If you have a nondairy sour cream brand that you love, you can use that, too. Just be sure it's the proper thickness, and that you like the taste of it, since baking only intensifies the flavor.
Eggs
There is one egg and one egg yolk in this recipe. You should be able to replace each of those with an appropriate amount of a “chia egg.”
In place of the full egg, use 1 full chia egg. In place of the yolk, use just one half. The total would be 1 1/2 tablespoons ground white chia seeds + 1 1/2 tablespoons lukewarm water, mixed and allowed to gel.
Sour Cream Gluten Free Sugar Cookie Bars
Ingredients
- 2 ¼ cups (315 g) all purpose flour gluten free flour blend, (I used Better Batter; please click thru for full info on appropriate blends)
- 1 teaspoon xanthan gum, (omit if your blend already contains it)
- ¾ teaspoon baking powder
- ½ teaspoon baking soda
- ¼ teaspoon kosher salt
- 12 tablespoons (168 g) unsalted butter, at warm room temperature
- ¾ cup (150 g) granulated sugar
- 1 (50 g) egg, at room temperature, beaten
- 1 (25 g) egg yolk, at room temperature, beaten
- 1 teaspoon pure vanilla extract
- 1 ½ cups (173 g) confectioners’ sugar
- ¾ cup (192 g) sour cream, at warm room temperature
- Vanilla sugar, for sprinkling (2 to 3 tablespoons) (See Recipe Notes).
Instructions
- Grease and line a 9-inch square baking pan or a 9-inch x 13-inch x 2-inch baking pan and set it aside. Preheat your oven to 350°F.
- In a medium-sized bowl, place the flour, xanthan gum, baking powder, baking soda, and salt, and whisk to combine well. Set the dry ingredients aside.
- In the bowl of a stand mixer fitted with the paddle attachment or a large bowl with a handheld mixer, place the butter and granulated sugar, and beat on medium-high speed until light and fluffy (about 5 minutes).
- Add the egg, egg yolk, and vanilla and beat to combine. Add the confectioners’ sugar, and beat until smooth, then the sour cream and beat again until smooth. Add the dry ingredients and mix until just combined. The cookie dough will be thick but relatively soft.
- Transfer the cookie dough to the prepared baking pan. Using a moistened spatula, spread it into an even layer in the prepared pan. Sprinkle the top evenly with a thin layer of vanilla sugar (about 3 tablespoons). Turn the pan toward each side to distribute the sugar evenly over the top.
- Place the pan in the center of the preheated oven and bake until set all the way to the center and a toothpick comes out clean (about 30 minutes for the square pan; about 22 minutes for the rectangular pan). Allow to cool completely in the pan before slicing into squares and serving.
Video
Notes
Nutrition information is automatically calculated, so should only be used as an approximation.
Happy New Year Nicole! I love these bar cookies! I baked them in a 9″ square pan and the batter raised perfectly. A nice mix of sugar cookie and not quite cake. I am one of your fans that cannot eat eggs and I am not happy with chia eggs (although I keep trying). For this recipe I used a starch egg and a tablespoon of greek style coconut yogurt for the egg yolk. Next time I will bake in a 9X13 pan to discover the texture difference. I am also thinking of lemon bar cookies.
I appreciate all your effort. Yes, the recipe development and blog is your job. And you produce for a mostly grateful public. I have been encouraged by you allowing us glimpses of your life. Thank you for your dedication.
Lari G
Hi, Lari, I wish there were a better egg substitute that was truly reliable—and colorless. If you’re really committed and industrious, I think you’d have better luck with a true flax egg, where you boil it and then strain out the pieces. That (forgive me) goo is really useful. But it’s a whole big process… And thank you so much for your kind words. I’m so glad the glimpses of life have been encouraging. All these years, and encouragement is still my #1 goal!
Hi, from Australia! I made this and it was delicious but more cake like and needed longer in the oven. Our ingredients are somewhat different here. I used ALDI gluten free flour. Everyone who tried it did not believe it was GF, LOL. I am going to try it with some ginger.
Thanks for your great recipes. I will be trying many more.
I recommend that you use my all purpose gluten free flour blend recipes. I’m not familiar with that gluten free flour blend in particular, but my recipes are only designed to work with one of my recommended blends, Sue. They aren’t all created equal, by any means.
these are excellent!
So glad, Karen!
Made these in a 9×13 pan. I do not eat a gluten free diet but before I packed these up for my friends I tasted one, then another! They really are quite good. Light tasting and they smell lovely when baking. Thank you for this easy recipe!
You’re very welcome, Margo! Those are some lucky friends. :)
Hi Nicole. Thank you for answering so quickly but I was basically just wondering if these should be stored in the fridge or at room temperature? Also how long should they stay fresh? Sorry if somehow I missed this information in your article.
Oh, I understand, Margo. I would seal them tightly and store at cool room temperature for about 4 days, and then freeze for longer storage. If you freeze them, be sure to eliminate any air in the packaging because that’s what causes freezer burn. Defrost at room temperature, still sealed. Hope that helps!
Going to try this recipe for some friends who eat gluten free. Can you tell me how to store them so I can add that information to their treat? Thanks.
I’ve frozen them with success, Margo, if that’s what you mean.
Hello, I love that your recipes are written by weight, and have such thorough explanations for substitutions and methods. I seem to be having the same issues as Leah McPhee, and would love to get to the bottom of it! Jiggly batter in a 9×13 pan, and I had to bake for about 40 minutes to have it set. It looks like pretty cake now, 1.5 inches tall. I know cup4cup is not your preferred flour for baking, but your website says it will work anywhere all purpose gf flour is called for. I’m wondering if that is what she used as well, and that could be the culprit? (I measured by grams where applicable and have an oven thermometer, just to cross those things off the list. I didn’t have unsalted butter, so I used salted and omitted the salt. Could that have done it?) Thanks for any help!
I don’t think that using salted butter, or using Cup4Cup should have caused anything like what you’re describing. If you made any substitutions of ingredients, even the ones that I suggest, that will almost certainly account for your results. I cannot possibly test every substitution, and in fact haven’t tested any of them (they’re suggestions) unless I specifically indicate otherwise. Beyond that, I have 3 more guesses (and this is reaching, because I’m not there with you, which makes this exercise nearly impossible!). 1. Was your butter too soft to beat with the granulated sugar until the mixture was light and fluffy? If your butter was too soft (perhaps if you warmed it in the microwave?), it won’t beat properly and you won’t be able to incorporate any air into it. 2. Your oven thermometer may no longer be properly calibrated (I replace them at least 2 times a year); 3. Did you use a low fat sour cream, or some alternative sour cream? That would introduce more moisture, and create the issue you’re describing. The photos and video are meant to show, as well as tell, so you can compare your ingredients and methods to mine. That’s all I can really offer!
Would like to be on your email listing.
Hi, Suzanne, I’m afraid you have to opt in to my emails yourself. I can’t do it for you! There’s a form in the sidebar to sign up, and if you fill out the the “save this recipe” form on any recipe, you’ll also tick a box that has you consent to receive my emails and you’ll be on the list that way. Happy to have you!
These look terrific! I’m glad to hear you’re putting together a shipping info sheet.. I’ll be looking for that. Question. I’d like to make these a little more festive with a bit of colorful sprinkles on top, but will they stick on that crackly top? Any suggestions?
Hi, Janet, I think sprinkles would actually bleed if they even stuck to the crackly sugar layer, since the crackly top is created when the sugar cooks in the oven. If you’d like to dress up a sugar cookie, I’d go with the “fancy drop sugar cookies,” “bakery-style sugar cookies,” or maybe the “soft frosted sugar cookies.” Just use the search function.
I’ve created a post on How To Ship Cookies, but published it only in the “members” area of my blog, which is a premium ad-free area. I’m working on being able to share the post with everyone, for free. Stay tuned!
My kids and I could not wait for this to cool. We broke off the crumbly sugared edges and our cake looked like a disaster. However – it was delicious! This will now be my go-to recipe. We loved the vanilla flavor, and want to experiment adding other flavors next time: lemon, orange, coffee. Maybe almond or maple. The sugared crust is the best part, but my son raves about the fluffiness of the batter.
I’m so glad you loved them, Clare! I love that you’ve made it as written, and now want to experiment. That’s the best way, because now you know what it should look, feel, and smell like. If you make a maple flavored topping, you should consider using maple flavoring in place of vanilla extract. It’s kind of expensive, but it smells sooo good and a little goes a long way!