Preheat oven to 350 degrees F. Grease and flour three 8 inch cake pans.
Combine milk and vinegar to make sour milk; set aside.
Sift together the flour, sugar, cocoa powder, baking soda, baking powder and salt. Set aside.
Whisk together the eggs, oil, coffee and vanilla in a large bowl. Stir in the sour milk. Gradually beat in the flour mixture, mixing just until incorporated.
Pour batter into prepared pans. Place pans on center rack and place a cookie sheet on lower rack just in case there are spill-overs. Bake for 22-25 minutes, or until a toothpick inserted into the center of the cake comes out clean. Cool completely before filling.
To assemble, place one cake layer on cake plate. Spread with about 1 cup whipped cream; top with about ¾ cup cherry topping. Top with second cake layer; repeat layers of whipped cream and cherry topping. Top with third cake layer. Frost side of cake with remaining whipped cream.
Filling: Drain cherries, reserving ¼ cup juice. Combine reserved juice, cherries, sugar and cornstarch in a 2 quart saucepan. Cook over low heat until thickened, stirring constantly. Stir 2 teaspoons butter and 1 teaspoon vanilla. Cool before using.
Whipped Cream: Combine whipping cream and confectioner's sugar in a chilled medium bowl. Beat with an electric mixer at high speed until stiff peaks form. Beat in vanilla