Peanut Butter Sheet Cake

INGREDIENTS
½ cup butter
½ cup vegetable shortening
1 cup water
½ cup peanut butter
2 cups sugar
2 cups flour
½ cup buttermilk
2 eggs
½ teaspoon soda
1 teaspoon vanilla
Peanut Butter Frosting
½ cup butter
6 Tablespoons milk
¼ cup peanut butter
3 cups powdered sugar
1 teaspoon vanilla

INSTRUCTIONS

1. Preheat oven to 400 degrees F.
2. Spray a 15x10x1 inch baking sheet.
3. Combine flour and sugar in mixing bowl and set aside.
4. In a large microwavable mixing bowl combine butter, shortening, and water. Cook for about 3½ minutes until butter and shortening are melted. Stir in peanut butter and return to microwave for 40 seconds. Stir until smooth. Add flour and sugar mixture to the hot liquid and stir well. Add buttermilk then baking soda, then eggs, and then vanilla, stirring after each addition.
5. Pour into baking dish and bake at 400 degrees F for 20-25 minutes or until a toothpick comes out clean.
6. Cool for five minutes.
7. Poke cake all over with fork to allow places for the frosting to ooze down into.

Frosting

1. In a small microwavable mixing bowl, combine butter and milk and heat until butter is melted. Add peanut butter and return to the microwave for 30 second. Add powder sugar and vanilla and mix well.

http://www.chef-in-training.com/2015/10/peanut-butter-sheet-cake/