1. Preheat oven to 350°F. Line two baking sheets with parchment paper. Set aside. 2. Whisk together the dry ingredients in a medium bowl. In a large bowl, cream together the butter, peanut butter, and brown sugar. Stir in the egg and vanilla. Add the flour in thirds and stir until smooth. Roll the mixture into golf ball?sized balls then use a fork to press down lightly. Bake for 10 minutes, rotating the pan halfway through baking time. Cool the cookies on a wire rack