Mix 2 cups flour, 2 cups sugar, ½ cup cocoa powder, 1 tablespoon baking soda, and 1 teaspoon salt in a large bowl.
Add 2 eggs, 1 cup buttermilk, 1 cup hot water, and ⅔ cup oil
Beat with a hand mixer until combined and smooth (it should be runny). Pour into a greased 11x15-inch baking dish.
Bake for 20 minutes, or until a toothpick inserted in the middle comes out clean.