These thick and chewy gluten free chocolate chip cookie bars are the easiest way to bake up everyone’s favorite chocolate chip cookies in a single square baking pan.
Cookie bars, cookies, and blondies
Everyone knows that bars like blondies are baked together in a pan and cookies are baked in individual portions, spaced apart from one another on a baking sheet. But the difference between blondies and cookie bars is a little more subtle (but important!).
Blondies, like brownies, are baked with as little flour as possible. In fact, the flour used is just enough to ensure that the bars hold together once sliced and, well, bitten.
Cookie bars, like cookies, have enough flour to make them chewy and less dense than brownies. When you make chocolate chip cookies into bars, though, we can use more liquid and make a loose batter that wouldn’t be possible if we were baking individual cookies. Plus, we get the convenience of baking them all together in one shot.
How to make these chocolate chip cookie bars
Like our chewy brownies recipe, these cookie bars have a gorgeous thin layer of meringue on top. When you bite into one, that layer shatters and gives way to the most lovely chewy bars.
To make the bars, first, melt the butter and sugars together in a saucepan. Then, allow that mixture to cool slightly before adding it to well-beaten eggs (+ egg yolk) and vanilla extract.
It’s important to beat that mixture really well before adding whisked dry ingredients (gluten free flour, cornstarch, baking soda, and salt) and then the chocolate chips. Adding additional chocolate chips to the very top of the batter (I just reserve about 1/5 of the chips in the recipe) also seems to help create that meringue on top.
Combined with the right balance of wet to dry ingredients, and of course the right flour blend, this method creates super thick and chewy gluten free chocolate chip cookie bars. Using half brown sugar and half white granulated sugar, and melting those ingredients together with the butter first, makes for the perfect texture.
How to make thinner bars
If you’d prefer to make bars that aren’t quite as thick, and maybe even cut them into sticks, you can bake the same cookie dough in a jelly roll pan. A quarter sheet pan is a rimmed baking sheet that measures 9-inches x 13-inches x 1-inch.
A jelly roll pan is slightly larger, measuring 10-inches x 15-inches x 1-inch. Those extra few square inches make a big difference in providing the cookie dough with enough space to bake without overflowing the pan.
Since the batter will be better exposed to the heat of the oven in a jelly roll pan, you’ll need less baking time. Instead of 40 minutes at 325°F, thinner bars will bake in about 30 minutes. Similar to cheesecake, the bars are done when they no longer jiggle much in the center.
Ingredients and substitutions
Dairy-free: To replace the butter in this recipe, I would try half (4 tablespoons) Earth Balance buttery sticks and half (4 tablespoons) Spectrum brand nonhydrogenated vegetable shortening. Or, if you have it available to you, Melt brand vegan butter typically works great as a butter substitute in baking.
Egg-free: There are two whole eggs in this recipe and one egg yolk. The two whole eggs may be able to be replaced with one “chia egg” each (1 tablespoon ground white chia seeds + 1 tablespoon lukewarm water, mixed and allowed to gel). Without the eggs, you’ll miss out on the crinkly brownie-style top, though.
The egg yolk, which helps to add richness and tenderness to the bars, is a bit harder to replace. You can try another tablespoon of unsalted butter or even a tablespoon of extra virgin olive oil. Feel free to experiment!
Cornstarch: The cornstarch in these cookies adds tenderness. If you can’t have corn, try replacing the cornstarch with an equal amount, by weight, of arrowroot or potato starch.
Thick & Chewy Gluten Free Chocolate Chip Cookie Bars
1 1/4 cups (175 g) all purpose gluten free flour (I used Better Batter)
1/2 teaspoon xanthan gum (omit if your blend already contains it)
1/4 cup (36 g) cornstarch
1/2 teaspoon baking soda
3/4 teaspoon kosher salt
8 tablespoons (112 g) unsalted butter, chopped
5/8 cup (125 g) granulated sugar
5/8 cup (136 g) packed light brown sugar
2 eggs (100 g, weighed out of shell) + 1 egg yolk (25 g), at room temperature
3/4 teaspoon pure vanilla extract
6 ounces semi-sweet chocolate chips
Preheat your oven to 325°F. Line an 8-inch square baking pan with nonstick aluminum foil, or regular heavy-duty aluminum foil and spray it with nonstick cooking spray. Set the pan aside.
In a small bowl, place the flour, xanthan gum, cornstarch, baking soda, and salt, and whisk to combine well. Set the bowl aside. In a medium-size, heavy-bottom saucepan, place the chopped butter, granulated sugar, and light brown sugar. Place the saucepan over medium-low heat and, stirring occasionally to prevent burning, melt the butter and sugar and bring to a gentle simmer. Remove the pan from the heat and set it aside to cool until no longer hot to the touch. You can immerse the bottom of the pan in some ice water, but take care not to let the water splash up into the pan and don’t cool so much that the butter resolidifies.
In a large bowl, place the eggs, egg yolk, and vanilla, and beat with a handheld mixer until foamy and lighter in color (about a minute). Add the cooled butter and sugar mixture, and beat very well until the mixture falls off the beaters in ribbons (about 3 minutes). Add the flour mixture to the bowl, stir until the streaks of flour disappear, then beat briefly to ensure that everything is combined. The mixture will be thickly pourable and very sticky. Add all but about 1 ounce of the chocolate chips, and mix until the chips are evenly distributed throughout the cookie dough.
Transfer the cookie dough to the prepared baking pan, and shake and spread it into an even layer in the pan. Scatter the remaining chocolate chips evenly over the top, and place the pan in the center of the preheated oven. Bake for about 40 minutes, or until the top no longer glistens or jiggles at all. Allow the bars to cool in the pan at room temperature for at least 10 minutes before placing them, still in the pan, in the refrigerator to chill until firm to the touch. Remove the cooled bars from the pan by holding onto the foil. Slice into 9 or 12 equal pieces, and serve.