gluten free cookie cake is the perfect sugar cookie but in bar form. it's soft but can hold up in your hand and is topped with a delicious buttercream frosting -- the perfect bite!

think of the most perfect sugar cookie. from the texture to the flavor, this cookie bar is everything you could ever dream of! now take that, and put it into bar form.
and now you have my gluten free cookie cake topped with a creamy vanilla buttercream frosting!
the cookie bars are soft, moist and filled with such a delicious flavor. it's hard to stop eating these because they are THAT good.
what's better than a sugar cookie? a THICK sugar cookie.
what's better than a thick sugar cookie? a thick sugar cookie WITH FROSTING!
now, let's make it.
main ingredients
- gluten free flour / regular all-purpose flour
- baking powder
- granulated sugar
- vanilla extract
- egg
- butter
- powdered sugar
- buttermilk
- sprinkles (optional, for topping)

tips for making these gluten free cookie cake bars
when making these bars, there are a few things you can do so that they come out perfect.
first of all, use real butter and make sure that it is softened to room temperature (not melted). you want to use real butter to make sure it gives both the cookie and frosting the richness you want in every bite.
next, you'll want to make sure that the sugar cookie base is completely cooled before adding the frosting. you don't want it to even be the slightest amount warm as that will cause the frosting to melt as soon as it touches the cookie base.
last but definitely not least, enjoy and savor every bite! these bars are truly heaven.
how to make sugar cookie bars
- preheat the oven to 350 degrees F
- line a square 8x8 baking pan with parchment paper
- cream together the butter, sugar, egg and vanilla extract until fluffy
- fold in the flour and baking powder until just combined. the batter should be on the thicker side but spreadable
- transfer the batter to the baking pan and spread it in an even layer
- bake in the oven for 20-22 minutes until the edges are golden and a toothpick comes out of the center clean
- let cool completely and in the meantime, make the vanilla buttercream
- to make the frosting, blend the powdered sugar, buttermilk, vanilla extract and butter together using an electric hand mixer
- the batter should be on the thicker side, add more powdered sugar if it is too loose and doesn't hold up on it's own
- once the sugar cookie base is cooled, remove it from the baking pan and add the frosting on top
- using a knife or offset spatula to spread the frosting in an even layer
- top with sprinkles if desired
- cut into 9 bars and enjoy


frequently asked questions
yes! i have made these with regular all-purpose flour and they come out great. for gluten free flour, i suggest using king arthur's gluten free flour or cup4cup's gluten free flour at a 1:1 ratio.
i love the buttercream frosting in the recipe card below. however, you can use your own favorite recipe or a store bought frosting as well!
yes, however, i would suggest using heavy cream or half and half over regular milk. if using any of these options, you will need to use less of the milk or more powdered sugar to thicken up the buttercream frosting.
the bars are done baking when the edges are golden and top of the bars is lightly golden. if you stick a toothpick in the center, it should come out clean if done as well.
store in an airtight container at room temperature for up to 5 days.
yes! you can freeze the dough for up to 1 month and thaw it out when you're ready to make the bars.
related recipes
- gluten free chocolate cupcake with sweet potato
- gluten free blondies
- bakery style brownies
- gluten free peanut butter blossoms
- low calorie brownies
- gluten-free m&m cookies
- honey sugar cookies

if you try this recipe, please consider leaving a rating and comment at the end of this blog post! it is incredibly helpful to my small business and to your fellow readers.

gluten free cookie cake with frosting
Ingredients
sugar cookie bars
- ½ cup salted butter softened
- 1 cup granulated sugar
- 1 large egg
- 2 tsp vanilla extract
- 1 ⅔ cups gluten free flour / regular all-purposes flour
- 1 tsp baking powder
vanilla buttercream frosting
- 16 oz powdered sugar
- ½ cup salted butter softened
- 2 tsp vanilla extract
- ¼ cup buttermilk or kefir
Instructions
- preheat the oven to 350 degrees F
- line a square 8x8 baking pan with parchment paper
- cream together the butter, sugar, egg and vanilla extract until fluffy
- fold in the flour and baking powder until just combined. the batter should be on the thicker side but spreadable
- transfer the batter to the baking pan and spread it in an even layer
- bake in the oven for 20-22 minutes until the edges are golden and a toothpick comes out of the center clean
- let cool completely and in the meantime, make the vanilla buttercream
- to make the frosting, blend the powdered sugar, buttermilk, vanilla extract and butter together using an electric hand mixer
- the batter should be on the thicker side, add more powdered sugar if it is too loose and doesn't hold up on it's own
- once the sugar cookie base is cooled, remove it from the baking pan and add the frosting on top
- using a knife or offset spatula to spread the frosting in an even layer
- top with sprinkles if desired
- cut into 9 bars and enjoy
These look so delicious.
Thank you so much - I hope you enjoy!