Chocolate Sheet Cake

I know that it's Thanksgiving week and I should probably be posting Thanksgiving-themed recipes, but to be completely honest I'm not that on top of things. Instead, I'm posting this recipe for my favorite-ever chocolate cake. My mom and grandma always made this when I was growing up, and every time I eat it I think of home and all of my happy memories from when I was little. I literally cannot leave myself alone with this cake or I will eat it and eat it and eat it one little piece at a time until suddenly the entire thing is gone. It's not much to look at, but it tastes incredible!

Chocolate Sheet Cake

Cake:

2 cups flour

2 cups sugar

½ tsp. salt

½ cup butter

½ cup shortening

1 cup water

½ cup buttermilk

1/4 cup unsweetened cocoa powder

1 tsp. baking soda

2 eggs

1 tsp. vanilla

Frosting:

½ cup butter

1/4 cup unsweetened cocoa powder

1/3 cup buttermilk

1 tsp. vanilla

2 ½ cups (approx.) powdered sugar

chopped walnuts and/or mini marshmallows (optional)

1. Preheat oven to 400 degrees. Spray jelly-roll pan with cooking spray.
2. In bowl of large stand mixer, combine flour, sugar, and salt.
3. In medium saucepan over medium heat, melt together butter, shortening, water, and cocoa powder. Stir frequently until well combined. Add to dry ingredients, mixing on medium speed until completely combine.
4. Add buttermilk, eggs, vanilla, and soda. Beat on medium speed until completely combined. Batter will be very thin.
5. Pour batter into prepared pan. Bake for 25 minutes, or until cake springs back when touched in the center. If using nuts and marshmallows, sprinkle evenly over top of cake. Frost while cake is still warm.
6. As soon as cake comes out of the oven, immediately prepare the frosting. Boil butter, cocoa, and buttermilk in large saucepan until slightly thick, 2-3 minutes after it begins to boil. Stir constantly. Remove from heat. Add vanilla and powdered sugar and beat with an electric mixer until frosting reaches spreading consistency. Immediately spread over warm cake (or pour, if using nuts and marshmallows as it simply won't spread over the top of those).