Chocolate Mint Pinwheels

1/2 cup shortening
1/2 cup butter, softened
1 cup sugar
1 egg
2 tablespoons milk
1 teaspoon vanilla
2 3/4 cups flour
1/2 teaspoon baking powder
1/4 teaspoon salt
1/2 teaspoon mint extract
1/4 teaspoon green food coloring (optional)
1/4 cup baking cocoa

In a large bowl beat shortening and butter until combined; add sugar and beat until fluffy. Add egg, milk and vanilla; beat well. Divide batter mixture in half.

In a separate bowl, combine flour, baking powder and salt.

Into one portion of batter, add half of the flour mixture, mint extract and green food coloring.

Stir baking cocoa and remaining flour mixture into the remaining batter; mix well.

Roll each portion between sheets of wax paper. Peel off the top sheets and place mint dough on top of chocolate dough. Roll up dough, jelly-roll fashion, removing bottom sheet of wax paper as rolled. Cut in half crosswise and refrigerate for 4 hours.

When dough is chilled, preheat oven to 375�F. Cut dough into �-inch slices and place 2 inches apart on an ungreased baking sheet. Bake for 8 to 10 minutes or until edges are firm. Let cool.