Ingredients
Equipment
Method
Prepare the dough
- Preheat the oven to 350°F and line two rimmed sheet pans with parchment paper.
- Whisk together 2 1/4 cups all-purpose flour, 1 teaspoon baking soda, 1/2 teaspoon salt, and 1/2 teaspoon cornstarch in a medium bowl.
- Cream 1/2 cup unsalted butter, 3/4 cup packed light brown sugar, and 1/4 cup granulated sugar until light, about 2–3 minutes, then add 1 large egg and 1 teaspoon vanilla and mix to combine.
- Beat in 1 1/4 cups creamy peanut butter until smooth, then add the dry ingredients on low and mix until just combined; chill 10–15 minutes if dough is sticky.
Shape and bake
- Portion dough with a small scoop or by tablespoon into oval mounds about 1 1/4 inches wide and place 1 1/2 inches apart on the prepared pans.
- Lightly press shallow ridges with a fork (or use a small cookie stamp) and bake one tray at a time at 350°F for 10–12 minutes until edges are set and lightly golden.
- Transfer cookies to a wire rack and cool completely before filling.
Make the filling
- Beat 1/2 cup unsalted butter with 1/2 cup creamy peanut butter until smooth, then gradually add 1 3/4 cups powdered sugar on low.
- Add 1 teaspoon vanilla, 2 tablespoons heavy cream, and 1 teaspoon cornstarch and beat until light and pipeable; adjust thickness with up to 1 additional teaspoon cream or a tablespoon more powdered sugar.
Assemble
- Pair cooled cookies by size and pipe about 1 teaspoon of filling onto the flat side of one cookie, then gently press the matching cookie on top.
- Let assembled sandwiches rest 10 minutes to set, then store in an airtight container in the refrigerator for up to 7 days.
Notes
If dough is too sticky chill for 10–15 minutes before shaping. Use creamy peanut butter in the filling for smooth assembly; chunky in the dough is optional. For transportable cookies, refrigerate assembled sandwiches briefly to firm the filling. Freezing unfilled cookies for up to 3 months works well; thaw before assembling.
