3 cups all-purpose flour
1-1/2 teaspoons baking powder
1/8 teaspoon salt
1 cup (2 sticks) butter, softened
1 cup granulated sugar
3/4 cup firmly packed light brown sugar
3 large eggs
1 teaspoon vanilla extract
1 (12 ounce) package semisweet chocolate chips
1 (11-1/2 ounce) package milk chocolate chips
1 (12 ounce) package white chocolate chips
1 cup coarsely chopped walnuts
1. Preheat oven to 350 degrees F. In a large bowl, combine the flour, baking powder and salt; set aside. In a separate large bowl, combine the butter, granulated sugar and brown sugar; beat with electric mixer on high speed until light and fluffy. Beat in eggs one at a time; stir in the vanilla.
2. Gradually add the flour mixture to the butter mixture, beating well after each addition. Fold in all three of the chocolate chips and the walnuts.
3. Drop dough by rounded tablespoonfuls about 2-inches apart onto ungreased baking sheets. Flatten the dough slightly with the back of a fork. Bake for about 15 minutes or until golden brown. Cool on baking sheets for 5 minutes; transfer to wire racks to cool completely. Makes 5 dozen cookies.