It's interesting how popular recipes travel across the country as they are shared among friends and family. This recipe comes from both sides of our family. It's a delicious retro chocolate sheet cake, also known as Texas Sheet Cake, and it's one of my favorites from childhood. I remember my mother making these for parties and potlucks, and they were always devoured. It's an easy cake for any occasion and one that I turn to regularly, like my banana Bundt cake or cinnamon apple cake.
The cake is loaded with chocolate flavor, which is enhanced by cooking the chocolate with butter and water before mixing in with the rest of the ingredients. You also cook the frosting on the stove and pour it over the cake while both are still hot, then let the cake and frosting cool. The cake has a consistency much like a brownie. It's absolutely decadent and very easy. I like to add a flavor boost with some instant espresso mixed in the dry ingredients.
For the cake, make sure that you are using natural unsweetened cocoa instead of Dutch process. Natural unsweetened cocoa still has the natural acids, which means that it only requires baking soda for the cake to successfully rise. Dutch process cocoa is treated with an alkali to remove the acids and make a more mellow chocolate, which means that you must use baking powder instead of soda in order for a cake to rise properly.
Make It Gluten Free
Due to gluten intolerance, I now make this gluten free. My favorite gluten-free flour blend is King Arthur Measure for Measure, which does really well in this recipe. I usually find it at our local Wal-Mart or Wegmans, though I have seen it in large bags at Costco. I also check all the other ingredients to verify that they are gluten free.
Gluten-Free Chocolate Sheet Cake, aka Texas Sheet Cake
- small sauce pan
- medium sauce pan
- stand mixer with paddle attachment
- 15-½ x 10-½ x 1 pan (aka jelly roll pan), greased and floured
- 2 cups King Arthur Measure for Measure gluten-free flour (or unbleached all-purpose flour)
- 2 cups granulate sugar
- 1 teaspoon baking soda
- 2 tablespoons ground espresso (optional)
- ½ pound unsalted butter
- 5 tablespoons natural unsweetened cocoa
- 1 cup water
- 1 teaspoon vanilla extract
- ½ cup buttermilk
- 2 eggs
- ¼ pound unsalted butter
- 2 ounces unsweetened baking chocolate (shaved)
- 3 ounces buttermilk
- 16 ounces confectioners sugar
- 1 teaspoon vanilla extract
- 1 cup chopped walnuts (optional)
- Preheat oven to 375° F / 190° C.
- Sift together flour, sugar and soda.
- Melt butter, cocoa and water in small pan over low heat. Bring to a boil and pour over dry ingredients.
- Blend together the vanilla, buttermilk and eggs. Add to the other ingredients and mix until thoroughly combine.
- Pour into a greased and floured 15-½ x 10-½ x 1 pan. Bake for about 20 to 25 minutes.
- About 10 minutes before cake is done, melt the butter, cocoa and buttermilk in medium pan. Bring to a boil for 1 to 2 minutes.
- Remove from heat and add the confectioners sugar, vanilla and nuts. Stir well.
- Pour over the hot cake and allow to set up. Cool completely.
- I've changed the frosting just a bit and substituted 2 ounces shaved unsweetened chocolate. It makes the rich frosting even richer. The original recipe calls for 5 tablespoons cocoa powder.
- The ground espresso is my addition. I like how the coffee plays with the chocolate.