Ingredients

• 2 1/2 cups confectioners' sugar, plus 1/2 cup
• 1 1/2 cups, plus 1 tablespoon ground almonds
• 2 1/2 tablespoons cocoa powder
• 5 egg whites
• 1/2 cup butter, at room temperature
• 1/2 cup peanut butter, at room temperature
• 1 cup confectioners' sugar
• 1/4 teaspoon vanilla extract

Instructions

1. Special equipment: Pastry bag with round tip
2. Make the Macaroons: Preheat the oven to 300 degrees F.
3. Line several sheet pans with parchment paper and set aside. In a bowl, combine 2 1/2 cups of the sugar, almonds, and cocoa powder.
4. In another clean dry bowl whip the egg whites with the remaining 1/2 cup sugar until medium peaks form (do not beat to stiff peaks). Fold egg whites into dry ingredients to a make a meringue. Fill the pastry bag with the meringue. (To easily fill the pastry bag, place it (with a clothespin holding it shut at the bottom) in a tall round container such as a coffee can, mayonnaise jar, or vase, folding the edge over the rim of the container.)
5. Pipe rows of kisses 1-inch in diameter (about the size of a quarter), keeping them 1/2 inch apart, onto the sheet pans. Bake until very light brown, rotating the pans after 8 minutes, about 17 minutes. Let the macaroons cool on the pan.
6. Meanwhile, make the Peanut Butter Buttercream: In a standing mixer fitted with a whisk attachment, cream the butter until light and fluffy. Add the peanut butter and whip. Add the confectioners' sugar and vanilla and whip until fluffy. Transfer the buttercream to a clean pastry bag fitted with a round tip.
7. Peel 2 macaroons off the parchment, pipe the buttercream on 1 flat side and sandwich the other flat-side down on top. Repeat with the remaining macaroons. Keep chilled in an airtight container until ready to serve.