Peanut Butter Sandwich Cookies

I want it. I want it in my tummy. 

Let us discuss this cookie. Let us discuss it in great detail, as it deserves.

You see, dear world, for anyone with an obsession with a certain popular cookie ("Mutter-Putters", anyone?), this is nirvana. Peanut-buttery, crunchy, creamy nirvana.

I can't even describe to you how delicious they would be with a tall glass of milk or even - dare I even go there - chocolate milk. Woah.

This is the kind of cookie that you made for a long Saturdays, a comfy corner of a couch, and a stack of comic books. This is the kind of cookie you make and don't tell anyone about. Or, conversely, this is the kind of cookies you make for bake sales. I made these for my church's yard sale last weekend, and 99% of them sold. Anything with a 99% success rate is worth giving a try!

Like so many things America's Test Kitchen does, these are incredible. They're actually pretty easy to make, they just take a bit of time to assemble.

Whatever you do, do not - I repeat DO NOT - taste the filling. It's diabolically addictive.

Peanut Butter Sandwich Cookies

The Best of America's Test Kitchen, 2013

Makes 24

Do not use unsalted peanut butter for this recipe

Cookies

1 1/4 cups (6 1/4 ounces) raw peanuts, toasted and cooled

3/4 cup (3 3/4 ounces) all-purpose flour

1 teaspoon baking soda

1/2 teaspoons salt

3 tablespoons unsalted butter, melted

1/2 cup creamy peanut butter

1/2 cup (3 1/2 ounces) granulated sugar

1/2 cup packed (3 1/2 ounces) light brown sugar

3 tablespoons whole milk

1 large egg

Filling

3/4 cup creamy peanut butter

3 tablespoons unsalted butter

1 cup (4 ounces) confectioner's sugar

For the cookies: Adjust oven racks to upper-middle and lower-middle positions and heat oven to 350

degrees. Line 2 baking sheets with parchment paper. Pulse peanuts in food processor until finely chopped about 8 pulses. Whisk flour, baking soda, and salt together in bowl. Whisk melted butter, peanut butter, granulated sugar, brown sugar, milk, and egg together in second bowl. Stir flour mixture into peanut butter mixture with rubber spatula until combined. Stir in peanuts until evenly distributed. 

Using #60 scoop or tablespoon measure, space 12 mounds evenly on each prepared baking sheet. Using damp hand, flatten mounds until 2 inches in diameter. 

Bake until deep golden brown and firm to touch, 15 to 18 minutes, switching and rotating sheets halfway through baking. Let cookies cool on sheets for 5 minutes. Transfer cookies to wire rack and let cool completely, about 30 minutes. Repeat portioning and baking remaining dough.

For the filling: Microwave peanut butter and butter together until butter is melted and warm, about 40 seconds. Using rubber spatula, stir in confectioner's sugar until combined. 

To assemble: Place 24 cookies upside down on counter. Place one level tablespoon (or #60 scoop) warm filling in center of each cookie. Place second cookie on top of filling, right side up, pressing gently, until filling spreads to edges. Allow filling to set for 1 hour before serving. Assembled cookies can be stored at room temperature for up to 3 days.

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