Pre heat your oven to 350° F. Line two large cookie sheets with parchment paper or silpat mats.
In a medium size mixing bowl, measure the flour, baking powder, baking soda, and salt. Blend them together well. Set aside for later.
1 ⅓ cup flour, ¾ teaspoon baking soda, ½ teaspoon baking powder, ¼ teaspoon salt
In a larger mixing bowl, cream your brown sugar, white granulated sugar, and butter with a hand mixer. Mix in the egg and the vanilla extract. Combine well.
½ cup butter, ½ cup granulated sugar, ½ cup light brown sugar, 1 large egg, 1 teaspoon vanilla extract
Add the peanut butter to the sugar and egg mixture. Blend well.
¾ cup peanut butter
Using your hand mixer, add the blended flour ingredients into the sugar, egg, and peanut butter mixture. Mix in well after each addition. When it gets thick, switch to a spatula.
Scrape the sides of the bowl clean, forming a ball of dough. Scoop out into 24 equal size scoops and form each into a ball. Using fork tines, flatten to ½" tall discs.
Place three Reese's Pieces candies on each cookie, pressing into the cookie gently. Place in the refrigerator for 30 minutes or freezer for 15. Remove chilled cookies and bake 8 to 9 minutes.
4 oz Reese's Pieces
Let sit to cool before transfering to a rack to cool completely. Enjoy!