Stained Glass Window Cookies

2/3 cup butter or margarine
1 cup white sugar
1/2 teaspoon vanilla extract
2 eggs
3 cups all-purpose flour
2 teaspoons baking powder
1/2 teaspoon salt
1/3 cup milk
40 pieces of colored hard candy

Preheat oven to 350F. Grease cookie sheets. In a large bowl, cream butter and sugar. Stir in vanilla and eggs. In another bowl, sift together flour, baking powder and salt; add to egg mixture alternately with milk. On a lightly floured surface, roll the dough 1/4 inch thick. Cut into 1/4 to ½ inch wide strips and, on a well-buttered baking sheet, form into window frames. Alternately, cut with graduated cookie cutters so that there is a hole in the middle of each cookie. Keeping the colors separate, place candy in plastic bags and crush into small bits. Place crushed candies inside window frames. Bake for six minutes, or until candy is just melted. Cool on baking sheet for 5 minutes, until candy is hard. Carefully lift cookies off baking sheet with spatula.