1. Beat butter and peanut butter in a large mixing bowl with an electric mixer on medium to high speed for 30 seconds. Add granulated sugar, brown sugar, baking powder, and baking soda; beat until combined, scraping sides of bowl occasionally. Beat in eggs and vanilla until combined. Beat in flour. Stir in rolled oats with a wooden spoon. Stir in chocolate kisses.
2. Drop dough from a #50 or #60 scoop, or from a tablespoon, 3 inches apart onto an ungreased cookie sheet. Slightly flatten dough with your hand, if desired. Bake in a 375 degree F oven about 8 to 10 minutes or until edges are lightly browned. Transfer to wire racks and cool. Store in an airtight container or plastic bag at room temperature up to 3 days. Makes 60 to 72 cookies.
Make-Ahead Tip: Cool cookies completely. In an airtight or freezer container, arrange cookies in a single layer; cover with a sheet of waxed paper. Repeat layers, leaving enough air space to close container easily. Freeze up to 1 month.