Chocolate Layer:
3 squares unsweetened chocolate
3/4 cup margarine
1 1/2 cups sugar
3/4 cup sifted flour
3 eggs
3/4 teaspoon vanilla

Melt chocolate and margarine and mix together. Add the other four ingredients and spread on a greased and floured 16-x11-inch jelly roll pan. Bake 12-17 minutes at 375 degrees. Let it cool.

Mint Layer:
1/3 pound butter
1 pound powdered sugar
2 teaspoons mint extract
a few drops of green food coloring

Cream these ingredients until they are light and fluffy. Spread on top of the cooled chocolate layer. Place in the refrigerator for about 30 minutes.

Topping:
2 squares semi-sweet chocolate
3/4 tablespoon shortening (solid, white)

Melt these ingredients in a small bowl above hot water. Drizzle over the mint layer. Cool and cut into squares.