Homemade Chocolate Sheet Cake with Boiled Chocolate Frosting
A deliciously rich homemade chocolate sheet cake with a boiled chocolate frosting. This is a classic chocolate sheet cake recipe can also be known as Texas Chocolate Sheet Cake.
Preheat the oven to 350. Prepare a large sheet pan (18x12x1) by greasing and flouring.
If you are using sour milk method- combine ½ cup milk with 2 tablespoon white vinegar and set aside. If you are using buttermilk you can skip this step.
In a large bowl combine flour, sugar and salt. Set aside.
In a saucepan over medium high heat bring to a boil 1 cup butter, 1 cup water, and 3 Tablespoons cocoa. Remove from heat and stir into the flour/sugar mixture. Next add 2 slightly beaten eggs (you may want to temper your eggs slightly with a tablespoon of the warm batter ), ½ cup sour milk, 1 teaspoon baking soda, and 1 teaspoon vanilla. Stir to combine. Pour into prepared sheet pan.
Bake for 18-22 minutes.
While the cake is baking prepare your frosting so it can be poured on as soon as the cake comes out of the oven.
In a saucepan over low heat mix together 1 cup butter, 3 tablespoon cocoa powder, 5 tablespoon milk, and 1 teaspoon vanilla. Stir until it is melted and then add the 3 ½ cups powdered sugar. Stir until it is well combined.
As soon as the cake comes out of the oven pour the frosting over the cake. Smooth with a offset spatula or knife. Let rest 1 hour for the frosting to set before serving.
Store at room temp, covered, for up to a week.
Notes
Sour Milk or Buttermilk:Either will work in this recipe.If you do not have buttermilk you can make your own by combining ½ cup milk with 2 tablespoon white vinegar, let it sit for a few minutes and then give it a stir.