Here's the recipe I have from from the book Best Recipes from the backs of boxes, Bottles, cans and jars by Ceil Dyer

HERSHEY'S FUDGE CAKE

"Perhaps this isn't the very first fudge cake recipe ever written but certainly it's one of the best, as two generations of good cooks will attest. Hershey Chocolate Company first printed it on their cocoa box label way back in the 1930's"

1/2 cup shortening
1 1/2 cups sugar
2 eggs
1 tsp. vanilla
1/2 cup plus 1 tbsp. hot water
2/3 cup Hershey's unsweetened cocoa powder
1 3/4 cup unsifted all-purpose flour
1 tsp. baking soda
1 tsp. baking powder
1 tsp salt
1 cup sour milk

Grease bottoms and sides of two (9-inch) layer pans.

Cream shortening and sugar until fluffy. Add eggs, one at a time, beating well after each addition. Blend in vanilla.

Stir hot water into cocoa to form a smooth paste; gradually add to creamed mixture. Combine flour, baking soda, baking powder, and salt; add alternately with sour milk to creamed mixutre. Pour batter into pans.

Bake at 350 degrees F for 30-35 minutes or until cake tester inserted in center comes out clean. Cool 10 minutes. Remove from pans; coll completely. Frost with your favorite frosting.