1. Heat oven to 375°F (190°C) or 350°F (180°C) for dark or nonstick cookie sheet.
2. In medium bowl, stir cookie mix, oil, water, and egg until soft dough forms. Stir in peanut butter candies. Drop by rounded teaspoonfuls 2 inches (5 cm) apart on ungreased cookie sheet; flatten slightly.
3. Bake 10 to 13 minutes or until light golden brown. Immediately top each cookie with 1 REESE PEANUT BUTTER CUPS Candy; press lightly into dough. Cool 2 minutes; remove from baking sheets. Let cookies stand until peanut butter cups are set before storing, about 3 hours.
Success: For even baking, make sure cookies are of the same shape and size.