2cupsall-purpose flour(280 grams) -- See note about flour
2teaspoonbaking powder
4teaspoonsbaking soda
1poundsalted butter, at room temperature**(480 grams)
⅔cupcreamy peanut butter
1cupgranulated sugar(200 grams)
1cupfirmly packed light brown sugar(200 grams)
2large eggs, room temperature(100 grams)
1 ½teaspoonsvanilla extract
⅓cupcoarsely chopped peanuts
2 ½cupsquick-cooking oats
Cookie Filling:
2sticksbutter, softened(240 grams)
1cupcreamy peanut butter(130 grams)
3cupsconfectioners' sugar plus a tiny bit more if needed(360
Instructions
Prepare Dough: In a bowl, mix together the flour, baking powder and baking soda; set aside.
Using an electric mixer, beat the butter and peanut butter. Add sugars and beat at medium speed for 3-4 minutes, scraping down bowl twice.
At low speed, add egg and vanilla. Add flour mixture and stir until well mixed, frequently scraping down bowl. Add peanuts (if using) and oats, and mix well. Using an ice cream scoop, scoop out 12 rounds of dough and put on plastic wrap lined dinner plates. Cover and chill for 30 minutes. After 30 minutes, shape dough into ¾ inch thick rounds.
Preheat oven to 350 degrees F.
Arrange rounds on parchment lined baking sheets spacing a good 4 inches apart.
Bake until cookies have spread and turned very light golden brown, about 10-14 minutes. Remove from oven and set aside to cool and firm up, 5 to 10 minutes. Transfer to a rack to cool completely before filling.
Filling: Using an electric mixer, beat the butter, peanut butter and confectioners' sugar until very smooth.
Assembly: Spread a thin layer (about ⅛ inch) on underside of a cookie. Sandwich with another cookie. Repeat.
Notes
Adapted from Frank Bruni in the New York Times, December 27, 2006The recipe doesn't call for added salt, so I think these would be best with salted butter. If you use unsalted, you might want to add ½ teaspoon to the doughIt's best to use 280 grams of flour because the cookies need it! Too much flour and they'll lose their crispness, but too little and they will spread too much and be greasy. It's best to weigh out the flour.