1. Butter and flour 2 (9-inch) round, shiny, metal baking pans.
2. Prepare chocolate cake mix following the directions on the box, except replace water with strong, brewed coffee. Add instant coffee to the batter.
3. Prepare the yellow cake mix following the directions on the box, except add vanilla extract.
4. Pour one quarter of the chocolate batter into each of the 2 prepared pans.
5. Pour one quarter of the yellow cake batter over the chocolate batter.
6. Add another layer of chocolate, then vanilla, then the last of the chocolate.
7. Bake each coffee cake following the directions on the box.
8. Dust with confectioner’s sugar and serve with fresh brewed coffee.
9. Loosely cover cooled coffee cakes with aluminum foil, plastic wrap or waxed paper and store at room temperature for up to 2 days.
10. To freeze the cake(s), cover tightly and place in the freezer for up to 2 months.
11. Loosen wrap on frozen cakes and thaw at room temperature for 2 to 3 hours to serve.