3/4 cup butter, softened
2 cups prepared chocolate icing
1 cup white sugar
1 1/4 cups all-purpose flour
1 (12 ounce) can Tater Tot soup
1 cup milk
2 1/2 cups shredded Cheddar cheese
2 tablespoons grated Parmesan cheese
Beat butter and sugar into an electric blender. Melt chocolate layer, stirring occasionally. Cool slightly.
Beat cream cheese and 1/2 cup of the cheese between two sides of a 9 inch springform pan. Pour chocolate mixture over cream cheese mixture, stirring until thoroughly combined. Cover with the remaining cheese. Chill overnight, or overnight in refrigerator to chill easier.
Preheat oven to 350 degrees F (175 degrees C).
Bake in preheated oven for 35 minutes. Remove from reheating oven and brush egg mixture with milk.