Bake the best ever recipe for moist gluten-free Texas sheet cake, topped with rich, fudgy chocolate icing. Originally my Aunt Jennie's family-favorite chocolate cake recipe, I've swapped ingredients to make this an easy gluten-free dessert anyone can make. The best part is you can't even tell it's gluten-free!
Legend has it that the first old-fashioned Texas sheet cake showed up in a Texas newspaper many years back. Unsurprisingly, it was an instant hit, and the rest is history.
I think just about everyone in my family would agree that this is the best chocolate cake, period. Maybe it's just the fact that this recipe has been passed down through the family over the years, or maybe it's also the fact that this cake originates from a large part of my family's home state, but Texas sheet cake will always hold a special place in my heart.
Better yet, this recipe is a gluten-free chocolate sheet cake, and it's not at all hard to go the extra mile and make it dairy-free. I've said it before, and I'll say it again: When gluten-free cakes are made right, you won't be able to tell the difference. In fact, I guarantee you won't even think this recipe is gluten-free once you've tasted it.
If you love sheet cake, you'll also love this deliciously easy lemon sheet cake. While you're at it, you might also check out my other moist and delicious chocolate cake recipe.
Why You'll Love This Recipe
- First of all, gluten-free Texas sheet cake is moist, rich, and highly addictive. This is NOT the kind of recipe you want to make if you're trying to shed a few pounds!
- This is a gluten-free version of classic Texas sheet cake. Guess what? It tastes no different from regular sheet cake. In fact, without your say-so, I guarantee that nobody will even be able to tell that it's gluten-free. Trust me, I've proven it with my own extended family.
- Old-fashioned Texas sheet cake is quick and easy. There is a little bit of stove time involved, but it's relatively short, and the recipe mainly involves mixing, baking, and lightly frosting!
- Gluten-free sheet cake is a crowd-pleaser. Not only is it absolutely delicious, but it is also not hard to make a lot of cake in a short amount of time!
Ingredient Notes
Let's talk about a few of the ingredients…
- Gluten-Free All-Purpose Flour – I almost always use Authentic Foods Classical Blend gluten-free flour. Time and time again, this flour blend has given me the best results and gluten-free baked goods that taste no different than the original. However, sometimes I do use Authentic Foods Steve's Gluten-Free Cake Flour Blend, especially for cake, cupcakes, or muffins. Cake flour can sometimes give a lighter, fluffier, and somewhat softer texture to sheet cake, but I find that all-purpose flour is generally sufficient. It's your call. I personally don't like to complicate my baking process any more than necessary.
- Xanthan Gum – I add xanthan gum to my flour to help give the cake a leavening agent. Some flours already contain xanthan gum, so be sure to check the ingredients before adding more. Too much xanthan gum and/or baking powder can give the cake a soapy flavor.
- Cocoa Powder – I prefer to use Hershey's cocoa powder. I appreciate the balanced sweetness it provides compared to a darker cocoa.
- Buttermilk – I use buttermilk to make this buttermilk Texas sheet cake, and I like to keep my favorite buttermilk mix on hand for recipes like this. The reason I like to use buttermilk instead of milk is that it helps give the cake rise, and without gluten in the cake, we can use any help we can get with rise. If you don't have any buttermilk on hand, you can make a 1:1 substitute by whisking vinegar and milk together. Use 1 tablespoon of vinegar per 1 cup of milk, and be sure to let it sit for 5-10 minutes, allowing it to curdle before using.
- Vanilla Extract – I always avoid imitation vanilla, instead opting for 100% real vanilla extract. In my opinion, real vanilla is far superior in flavor.
How to Make Gluten-Free Texas Sheet Cake
Before getting started, pre-heat the oven to 350ºF and grease a 16x10x1 sheet cake pan (or jelly roll pan). To make the recipe, just follow these steps.
For the Cake…
- In a large mixing bowl, whisk together the flour, xanthan gum, baking soda, sugar, and salt.
- In a medium saucepan, melt the butter.
- Then add the cocoa powder and water, whisking together.
- Bring this mixture to a boil over low to medium heat.
- Then pour the cocoa mixture over the dry ingredients.
- Add the buttermilk, eggs, and vanilla extract, mixing well 'til everything is well-combined.
- Pour the cake batter into the greased sheet cake pan, and bake at 350ºF for 25-30 minutes, or until a toothpick or cake tester inserted into the center comes out clean.
For the Frosting…
- While the cake is baking, melt the butter in a medium saucepan.
- Whisk the cocoa powder and buttermilk into the butter.
- Bring this mixture to a boil over low to medium heat.
- Remove it from the heat, and whisk in the powdered sugar, vanilla extract, and nuts, if desired.
- Mix or whisk 'til the mixture creates a smooth chocolate frosting.
- Then pour the frosting over the cake while it's still hot, spreading the frosting all over the cake 'til even and smooth.
- Once it's cooled, it's finally time to slice, serve, and enjoy! (Although Tip: I love enjoying a piece of this cake while it's still slightly warm and gooey.
Expert Tips and Recipe FAQ's
The primary difference is in the size of the pan. While a regular cake is typically baked as either a single layer in a 9×13 baking dish, or as a double layer in 2 8-9″ round cake pans, sheet cake is baked in a large, shallow sheet cake pan. For this recipe, that's a 16x10x1 pan.
Yes, it is entirely possible to make this recipe dairy-free. To do this, you'll have to cut out both the salted butter and buttermilk. Dairy-free butter substitutes include vegan butter, Earth Balance sticks, vegetable oil, canola oil, coconut oil, applesauce, and even some mayonnaise! All of these make for a fine 1:1 substitute. You can make a homemade buttermilk substitute with almond milk or other dairy-free milk. To make the buttermilk with almond milk, just add 1 tablespoon of vinegar per 1 cup of milk, whisking together well. Let this mixture sit for a few minutes, and it will begin to curdle and subsequently sour; that's when you know it's ready to use!
You may notice that this recipe uses a lot of fat in the forms of butter, oil, or buttermilk; this is what keeps a gluten-free cake moist. In fact, there's very little difference between this cake and a regular Texas sheet cake made with gluten flour. However, due to the fact that most gluten-free products have a naturally shorter shelf life, proper storage in an airtight container, as I will talk about below, is essential for maintaining that moisture content.
Seeing as this recipe uses a buttermilk icing, it is best that you store your finished cake in an airtight container in the refrigerator for up to 2-3 days. After that, it will start to lose its texture and can even grow more dense.
Yes, you can freeze it, provided that you hold off on frosting the cake until after it comes out for consumption. Most buttermilk frostings do not hold up well to freezing conditions over long periods of time. Stored in an airtight container or freezer bag, it should last for up to 3 months in the deep freeze. To thaw, simply leave it out on the counter for a couple hours before frosting. Once properly thawed and frosted, it's ready to eat!
More Gluten-Free Desserts You'll Love
Even if some of these are not gluten-free, you can easily switch up the ingredients to make them gluten-free just like this chocolate sheet cake.
- Grandma's chocolate gobs are a recipe you can make gluten-free by subbing in a gluten-free flour. Just be sure to check all your other ingredients to make sure they're gluten-free, as well.
- Slice off a piece of this delicious gluten-free lemon pound cake and enjoy every bite.
- Bake a gluten-free angel food cake to go with strawberries and other fresh fruit in season.
If you try this recipe, why not leave a star rating in the recipe card right below and/or a review in the comment section further down the page? I always appreciate your feedback. You can also follow me on Pinterest, Facebook, YouTube, and Instagram. And subscribe to my email list too!
Aunt Jennie's Gluten-Free Texas Sheet Cake
Ingredients
Cake
- 2 cups gluten-free all-purpose flour
- 1/4 teaspoon xanthan gum
- 1 1/2 teaspoon baking soda
- 2 cups sugar
- 1/2 teaspoon salt
- 16 tablespoons salted butter
- 4 tablespoons cocoa powder
- 1 cup water
- 1/2 cup buttermilk
- 2 large eggs
- 1 teaspoon vanilla extract
Frosting
- 8 tablespoons salted butter
- 4 tablespoons cocoa powder
- 6 tablespoons buttermilk
- 3 1/2 cups powdered sugar
- 1 teaspoon vanilla extract
- 1 cup nuts optional
Instructions
Cake:
- Pre-heat the oven to 350º F and grease a 16x10x1 sheet cake pan.
- In a large mixing bowl, whisk together the flour, xanthan gum, baking soda, sugar, and salt.
- In a medium saucepan, melt the butter.
- Then add the cocoa powder and water, whisking together.
- Bring this mixture to a boil over low to medium heat.
- Then pour the cocoa mixture over the dry ingredients.
- Add the buttermilk, eggs, and vanilla extract, mixing well 'til everything is well-combined.
- Pour the cake batter into the greased sheet cake pan.
- Bake at 350º F for 25-30 minutes, or until a toothpick or cake tester inserted into the center comes out clean.
Frosting:
- While the cake is baking, melt the butter in a medium saucepan.
- Whisk the cocoa powder and buttermilk into the butter.
- Bring this mixture to a boil over low to medium heat.
- Remove it from the heat, and whisk in the powdered sugar, vanilla extract, and nuts, if desired.
- Mix or whisk 'til the mixture creates a smooth chocolate frosting.
- Then pour the frosting over the cake while it's still hot, spreading the frosting all over the cake 'til even and smooth.
- Once it's cooled, it's finally time to slice, serve, and enjoy!
