Ho Ho Cake

1 (18.25 ounce) box chocolate fudge cake mix

Filling
3/4 cup granulated sugar
1/2 cup butter (stick, not tub), at room temperature
2/3 cup Crisco
Pinch of salt
2 teaspoons vanilla extract
1 (5 ounce) can evaporated milk

Topping
1 plastic can ready-to-spread chocolate fudge frosting

Bake cake according to package directions in a 15 1/2 x 10 1/2 x 1-inch baking pan. Cool

Beat filling ingredients for 10 minutes on high speed until fluffy and smooth. Spread over cooled cake.

Microwave the plastic can of frosting for 1 minute. Stir and pour over cake.