Ingredients
10 tablespoons (1 1/4 sticks) unsalted butter, room temperature
1 1/3 cups granulated sugar
1 large egg yolk
1 1/2 cups all-purpose flour, (spooned and leveled)
1/2 cup cocoa powder
1 teaspoon baking powder
1/2 teaspoon baking soda
1/2 teaspoon coarse salt
1/4 cup Caramel Sauce for Chocolate Pudding Cakes, cooled
3/4 cup (1 1/2 sticks) unsalted butter, room temperature
1 1/2 cups confectioners' sugar
Preparation
Preheat oven to 375 degrees, with racks in upper and lower thirds. In a large bowl, beat together butter and sugar with a wooden spoon or electric mixer until pale and fluffy; stir in egg yolk.
In another bowl, whisk together flour, cocoa powder, baking powder, baking soda, and salt; stir flour mixture into butter mixture until a dough forms. Drop dough by level teaspoons, 1 inch apart, onto 2 parchment-lined baking sheets.
Bake until cookies are puffed and cracked, about 8 minutes, rotating sheets halfway through. Remove sheets from oven and tap firmly on a counter to flatten cookies. Transfer cookies to wire racks and let cool completely. (To store, keep in an airtight container, up to 3 days.)
Make frosting: In a bowl, beat together caramel and butter with a wooden spoon until smooth; gradually beat in confectioners’ sugar until smooth. Spread frosting on flat sides of half the cookies and top with remaining cookies.
