Cream butter and brown sugar together in mixing bowl until light and fluffy. Add egg, vanilla, and peanut butter; beat well. Stir in flour. Cover and refrigerate for 1 hour. Preheat oven to 375. Shape chilled dough into 1-inch balls; arrange one inch apart on ungreased baking sheet. Bake for 5 minutes. Remove from oven and press a chocolate kiss in center of each cookie. Return to oven and bake for 3 to 4 minutes, being careful not to burn chocolate. Cool on wire racks.

* Note: If using Martha White All-Purpose Flour, sift 2 teaspoons baking powder and 3/4 teaspoon salt with flour.