Gluten Free Cookie Bars

This recipe for thick and chewy gluten free cookie bars makes everyone’s favorite thick and chewy gluten free chocolate chip cookies in a single square baking pan without sacrificing any texture. Plus, you get the crackly top of brownies!

Chocolate chip gluten free cookie bar on a round dark gray plate with a glass of milk and more cookie bars in the background.

Why this recipe works

These bars have all the chewy texture and classic taste of chocolate chip cookies without the fuss of having to shape and bake them individually.

If you just baked chewy chocolate chip cookie dough in pan, your bars would come out dense and tough. This recipe uses melted butter like gluten free brownies or gluten free blondies for chewiness, but more flour so the bars aren’t fudgy.

Using a combination of white and light brown sugars ensures that the flavors are just like you expect.

Recipe ingredients

Here’s what you’ll need to make these bars. For full ingredient amounts, scroll down to the recipe card below.

Overhead view of eggs, GF flour mixture, salt, butter, baking soda, white sugar, vanilla, light brown sugar, and chocolate chips labeled on a light surface.

Gluten free flour: A well-balanced blend of gluten free flours with finely ground rice flour as a base, plus xanthan gum and cornstarch for tenderness, provides most of the structure for the bars. I recommend Better Batter’s original blend and Nicole’s Best multipurpose most; Bob’s Red Mill gluten free 1-to-1 should also work well.
Baking soda: Helps the bars brown in the oven.
Salt: Brightens the other flavors, keeps them from tasting flat.
Granulated (white) sugar: Adds sweetness, and locks in moisture for tender cookie bars.
Light brown sugar: Also adds sweetness and tenderness, plus the molasses flavor adds color and provides that classic chocolate chip cookie taste.
Butter: The water in the butter, when heated, is released and dissolves the sugars completely.
Eggs and yolk: The whole eggs provide rise and enough structure to hold the rise as the bars cool; the extra egg yolk helps keep the bars moister for longer, and makes the bars more dense.
Vanilla: Adds depth of flavor.
Chocolate chips: Add chocolate flavor, and a contrasting texture when they resolidify after the bars cool.

single brown cookie bar square with chocolate chips on small round pewter plate

This overview illustrates how to make these bars in your own kitchen, with the reason behind each step.

Melt butter and sugars
Melt the light brown and granulated sugars with chopped butter over medium-low heat just until the butter is melted and the mixture simmers lightly. The sugars will dissolve into the liquid from the butter, which is part of what leads to the shiny, crackly top after baking. Let the mixture cool until it’s not hot to the touch so it doesn’t cook the eggs in the next step.

Beat the eggs plus butter and sugars
Beat two eggs and one egg yolk in a large mixing bowl until foamy, so the egg proteins can fully combine with the cooled sugar and butter mixture. These ingredients together will rise to the top of the bars during baking, and bake into a crispy, thin crackly layer.

Whisk the dry ingredients
Whisk together the gluten free flour blend with xanthan gum and cornstarch plus baking soda and salt, to avoid any bitter clumps in the bars.

Add dry to wet ingredients
Add the dry ingredients all at once to the wet ingredient mixture. The mixture will go from being very thin to thick and sticky as the flour mixture thickens the batter.

Add the chocolate chips
Add almost all of the chocolate chips, leaving out about 1 ounce, so you can scatter them on top.

Transfer to the pan
Scrape the batter into a pan lined with nonstick aluminum foil, or foil sprayed with cooking oil. Spread the batter into an even layer using a moistened offset spatula or butter knife so it bakes evenly.

Top with rest of chips and bake
Scatter the remaining chocolate chips evenly on top and bang the pan a few times on the counter so the chips stick to it. Bake at 325°F for 40 minutes, or until the top is lightly golden brown all over and the top doesn’t jiggle at all when you move the pan. Baking it low and slow ensures that the bars are golden brown all over, never too dark or burned.

Chill before slicing
The bars are too fragile to remove from the pan until they’re fully cooled and set. Let them cool in the pan until warm room temperature, then chill until firm before slicing. It will make slicing easy and clean.

Expert tips

Try making the bars thinner

You can bake the same cookie dough in a jelly roll pan. It’s slightly larger than a quarter sheet pan, measuring 10-inches x 15-inches x 1-inch. That provides the cookie dough with enough space to bake without overflowing the pan. Instead of 40 minutes at 325°F, thinner bars will bake in about 30 minutes. Similar to gluten free cheesecake, the bars are done when they no longer jiggle much in the center.

Don’t overcook the sugar

Brown sugar has a tendency to harden if you overcook it. So when you’re melting the butter and sugars, stop as soon as it reaches a very gentle simmer.

Line the pan with nonstick foil

Since the batter is thick and sticky, it can be difficult to spread it around if you line the pan with parchment, which tends to move and shift. Since the bars will stick to regular foil, either line the pan with nonstick foil, or spray cooking oil on regular foil.

Two stacked chocolate chip cookie bars on a dark plate with more cookie bars in the background.

Ingredient substitutions

Dairy free

To replace the butter in this recipe, try Melt, Miyoko’s, or Trader Joe’s block-style vegan butter. Or try half (4 tablespoons) Earth Balance buttery sticks and half (4 tablespoons) Spectrum brand nonhydrogenated vegetable shortening. And make sure your chocolate chips and flour blend are dairy-free.

Egg free

The two whole eggs may be able to be replaced with one “chia egg” each (1 tablespoon ground white chia seeds + 2 tablespoons lukewarm water, mixed and allowed to gel). Without the eggs, you’ll miss out on the crinkly brownie-style top, though. For the egg yolk, try 1 tablespoon of extra virgin olive oil.

Corn free

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, or just use more all purpose gluten free flour and make sure it’s corn-free.

Chocolate chip cookie bar on a small dark gray round plate with a glass of milk and another plated cookie bar in the background.

Storage instructions

These bars will keep for at least 5 days in a sealed container at room temperature, and up to a week in the refrigerator. For longer storage, place in freezer-safe zip top bags and freeze for up to 3 months. Defrost at room temperature or quickly in the microwave.

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.
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, and mix until the streaks of flour disappear, scraping the sides of the bowl frequently. The mixture will be thickly pourable and very sticky.
Add 5 ounces of the chocolate chips, reserving the final ounce to go on top. Mix by hand until the chips are evenly distributed throughout the cookie dough.
Transfer the cookie dough to the prepared baking pan, and use a moistened offset spatula or knife to spread it into an even layer in the pan.
Scatter the remaining chocolate chips evenly over the top and bang the pan on the counter a few times so the chips stick and sink down a bit.
Bake in the center of the preheated oven for about 40 minutes, or until the top is lightly golden brown all over, and no longer glistens or jiggles at all when the pan is moved gently.
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, about 30 minutes.
Remove the cooled bars from the pan by holding onto the foil. Slice into 9 equal pieces, and serve.

Gluten free flour notes
This recipe works best with Better Batter’s original all purpose blend or Nicole’s Best multipurpose with added xanthan gum. It should also work with Bob’s Red Mill 1-to-1 in the blue bag.
To make your own high-quality gluten free flour blend, check out my mock all purpose gluten free flour blends.