This version of a well-loved combination from childhood concentrates the flavors into a sweet dessert that appeals to all ages. We like strawberry jam, but feel free to substitute any flavor you prefer

　　

Ingredients

makes about 3 dozen

　　1 cup (2 sticks) unsalted butter, room temperature, plus more for pan

　　3 cups all-purpose flour, plus more for pan

　　1 1/2 cups sugar

　　2 large eggs

　　2 1/2 cups smooth peanut butter

　　1 1/2 teaspoons salt

　　1 teaspoon baking powder

　　1 teaspoon pure vanilla extract

　　1 1/2 cups strawberry jam, or other flavor

　　1 cup salted peanuts (5 ounces), roughly chopped

　　

Step 1

Preheat oven to 350°F. Butter a 9 by 13-inch baking pan, and line the bottom with parchment paper. Butter the parchment, dust with flour, and tap out excess.

　　

Step 2

Place butter and sugar in the bowl of an electric mixer fitted with the paddle attachment. Beat on medium speed until fluffy, about 2 minutes. With mixer running, add eggs and peanut butter; beat until combined, about 2 minutes. Whisk together flour, salt, and baking powder. Add to the butter mixture, and beat on low speed until combined. Add vanilla.

　　

Step 3

Transfer two-thirds of mixture to prepared pan; spread evenly with an offset spatula. Using offset spatula, spread jam on top of peanut-butter mixture. Crumble remaining third of peanut butter mixture on top of jam. Sprinkle evenly with peanuts.

　　

Step 4

Bake until golden, 45 to 60 minutes, rotating halfway through. Tent loosely with foil if bars are getting too dark. Transfer to a wire rack to cool. Run knife around edges and refrigerate, 1 to 2 hours. Cut into about thirty-six bars (about 1 1/2 by 2 inches). Cookies can be stored in airtight containers at room temperature up to 3 days.

　　Martha Stewart's Cookies