This Texas Sheet Cake recipe is THE ONE, you guys! As in, the only one you will ever need. Sour cream in the cake and the glaze, brown sugar, and extra cocoa make this the BEST chocolate sheet cake of your life!!
Preheat your oven to 350 degrees F. Line a jelly roll pan* with parchment paper, or spray well with nonstick spray.
In a medium or large saucepan, add 1 cup butter, 1 cup water, and 1/2 cup cocoa. Bring to a boil over medium high heat. Once it boils, take it off the heat.
Let it cool for a minute or two, then stir in brown sugar and 2 teaspoons vanilla.
Meanwhile in a medium bowl combine 2 cups flour, 1 cup granulated sugar, salt, and baking soda.
Add the dry ingredients to the saucepan. (Then wipe out the bowl and put it back in your cupboard.)
Stir well, then add 1/2 cup sour cream and eggs. Blend well until all the lumps are gone.
Pour the batter into the prepared pan and spread evenly to the sides.
Bake at 350 for about 18-20 minutes* (check times below), until a toothpick comes out of the center with no wet batter on it. The sides of the cake should just be starting to pull away from the edge of the pan. Don't over bake!
Meanwhile, make the frosting. Clean out the saucepan you used for the batter** and add 1 stick of butter and 1/4 cup cocoa. Stir together over medium heat until it comes to a boil, then remove from the heat.
Add 6 tablespoons sour cream and 1 teaspoon vanilla extract.
Use a whisk to stir in the powdered sugar. If your cake is not done baking when you finish the glaze, stir it every now and then to break up the hardened shell on top.
When the cake is done, take it out of the oven and let cool for 15-20 minutes. Spread the glaze over the cake.
Serve this with milk. No, seriously.
*The size of your jelly roll pan is a matter of debate. You can make this cake in a 9x13 inch cake pan (thick cake), a 10x15 inch jelly roll pan (thinnish cake) or an 12x18 inch half baking sheet (thinnest cake). I prefer the 12x18. The first time I made it, I did it in a 10x15, and found myself only wanting to eat the top half of my slice of cake so that there was a higher ratio of frosting. (The photos of this cake is of one that was baked in a 10x15.) The 12x18 gives you the perfect ratio of cake to frosting in my opinion.If you are baking this in a 9x13 bake for 23-25 minutes. If you do a 10x15, bake for about 20 minutes. If you bake it in a 12x18, bake for about 18-20 minutes.All of these times are going to vary because everyone's oven is different.** I actually never do this. I just start making the frosting in the same pan without washing or even wiping it out. The danger is that the remaining batter up the sides of the pan that you couldn't scrape out all the way could scorch. I use the butter to rub the sides of the pan occasionally to avoid this. I can't even believe I added this note, probably washing the pan is easier! These are the kind of risks that make me feel like I'm living a dangerous life.