Place 36 - 40 unwrapped mini peanut butter cups on a large plate or small baking sheet. Chill them in the freezer while preparing and baking the cookie dough.
36 - 40 mini peanut butter cups
In a mixing bowl whisk together the flour, baking soda and salt until well combined. Set aside for now.
1¾ cup (210 g) all purpose flour, ¾ teaspoon baking soda, ½ teaspoon salt
In a large mixing bowl fitted with paddle attachment, cream the butter with the peanut butter until smooth and well combined. Add the light brown and granulated sugars and mix on medium speed until smooth and well combined. This takes about 2 -3 minutes.
½ cup (113 g) unsalted butter, soft but still cool to the touch , ¾ cup (192 g) creamy peanut butter , ½ cup (100 g) granulated sugar, ½ cup (100 g) light brown sugar
On low mix in the egg and vanilla extract until smooth and well combined. Stir the dry ingredients into the wet until just combined. Cover the cookie dough in plastic wrap and transfer to the fridge to rest and chill for 30 minutes while the oven preheats.
1 large egg, room temperature, 1 teaspoon vanilla extract
Preheat the oven to 375 F (190 C) for 30 minutes before baking the cookies. Grease each cavity of a 24 count mini muffin pan. Using a small cookie scoop (1 tablespoons, 15 ml), scoop the pb cookie dough into a ball. Place the cookie dough balls into the prepared mini muffin pan.
Bake at 375 F (190 C) for 8 minutes. The cookie dough will puff up and fill the mini muffin cavities. As soon as the peanut butter cookie dough is pulled from the oven, press a chilled mini peanut butter cup down into the center of each cookie. Allow the pan to cool to room temperature for 30 - 60 minutes. Transfer the cooled muffin pan to the fridge to chill for 30 minutes. Remove the pan from the fridge and use the end of a butter knife to gently pry the cookie cups from the pan.