Beat butter and shortening in a mixing bowl. Gradually add sugar, beating well. Stir in egg, milk, and vanilla. Combine flour, baking powder and salt; gradually add to creamed mixture mixing well. Add a small amount of red food coloring to color dough as desired, beating until blended. Shape dough into a ball; cover and chill at least 3 hours. Divide dough in half; store one portion in refrigerator. Roll remaining portion to 1/4″ thickness on a lightly floured surface. Cut dough with a 3″ round cookie cutter; cut circle in half. Place on an ungreased cookie sheet or use Silpat on cookie sheet. Press several chocolate mini morsels in each cookie. Repeat with remaining dough. Bake at 375° for 8 to 10 minutes (do not brown). Cool on wire racks. Combine powdered sugar and water, mixing until smooth. Add a small amount of green food coloring, mixing until blended. Dip round edge of each cookie in green frosting, and place on wax paper until frosting is firm. Yield 3 dozen.