Reese's Pieces Peanut Butter Fluffernutter Cookies with Peanut Butter Buttercream
The cookies are a peanut butter lover’s dream: Peanut butter in the dough, in the Reese’s Pieces, and in the buttercream. The cookie dough is supremely soft, the Reese’s Pieces add crunch, the chocolate chips are melty and soft, and the marshmallows are like biting into clouds. Clouds that are topped with frosting from the heavens. It’s light, soft, fluffy, and lends even more squishiness to already supremely soft, moist, tender, gooey cookies. They’re some of the best cookies I’ve ever made.
about 12 to 15 large marshmallowseach sliced in half
Peanut Butter Buttercream Frosting
4tablespoonsunsalted buttersoftened (half of one stick)
about 1/3 cup creamy peanut butter
¾teaspoonvanilla extract
about 1 cup confectioners’ sugar
pinchsaltoptional and to taste
splash of cream or milkonly if necessary to achieve desired consistency
chocolate sprinklesoptional for garnishing
Instructions
For the Cookies – To the bowl of a stand mixer fitted with the paddle attachment (or large bowl and electric hand mixer), cream together the first 5 ingredients (through vanilla) on medium-high speed until light and fluffy, about 5 minutes.
Stop, scrape down the sides of the bowl, and add the flour, baking soda, optional salt, and mix on low speed until just incorporated, about 1 minute; don’t overmix.
Add the Reese’s Pieces, chocolate chips, and mix until just incorporated.
Using a medium 2-inch cookie scoop, form heaping two-tablespoon mounds (I made 27). Place mounds on a large plate, flatten mounds slightly, cover with plasticwrap, and refrigerate for at least 2 hours, or up to 5 days, before baking. Do not bake with warm dough because cookies will spread and bake thinner and flatter.
Preheat oven to 350F, line a baking sheet with a Silpat or spray with cooking spray. Place mounds on baking sheet, spaced at least 2 inches apart (I bake 8 cookies per sheet) and bake for about 6 1/2 minutes. Cookies will be at the extremely under-done point.
Remove tray from oven, and place a marshmallow halve on top of each cookie, pressing it down lightly into the cookie. Don’t press too hard and flatten the cookie.
Return baking tray to oven and bake for about 2 more minutes, until edges have set and tops are just beginning to set, even if slightly undercooked, pale and glossy in the center (hard to tell with the marshmallows covering the centers, I realize). Do not overbake because cookies will firm up as they cool. Allow cookies to cool on the baking sheet while you make the frosting.
For the Peanut Butter ButtercreamFrosting – To a medium mixing bowl, combine the butter, peanut butter, vanilla, and whisk to combine or beat with an electric mixer until smooth.
Slowly add the sugar, optional salt, and mix until smooth. Based on desired consistency of frosting, add the sugar slowly, and if you’ve added too much and the frosting gets too thick, add a splash of cream or milk to thin it.
Add a generous dollop (2+ tablespoons) to each cookie, and smooth it, as desired, with a knife or spatula.
Optionally garnish with sprinkles.
Cookies will keep airtight at room temperature for a few days or in the refrigerator for up to 1 week. I’m okay with leaving buttercream at room temperature for a couple days; if you aren’t, refrigerate the cookies, knowing they won’t have the gooey factor. Unbaked cookie dough can be stored airtight in the refrigerator for up to 5 days, or frozen for up to 4 months, so consider baking only as many cookies as desired and save the remaining dough to be baked in the future when desired.