Biscoff Buttercream Snickerdoodle Whoopie Pies

Instructions

1. Preheat the oven to 350 degrees. Spray two large baking sheets with nonstick cooking spray. In a large mixing bowl, beat together the butter, 1 cup light brown sugar, the egg and vanilla until light and fluffy. Combine the baking powder, baking soda, salt, and flour in a large bowl. Add the flour mixture to the butter mixture alternately with the buttermilk, beating on medium speed until combined, stopping to scrape down the sides several times.
2. Stir together 1/2 cup sugar and the cinnamon in a small bowl. Drop the dough by a 1/4 cup measure ice cream or cookie scoop into the cinnamon sugar mixture and coat all sides using two spoons (dough will be sticky). Place onto the baking sheets spacing about 3 inches apart. Bake for 15 minutes, until they’re set and firm to the touch. Remove from oven and cool completely on pans.
3. Meanwhile, beat the 1 1/2 sticks butter, the Biscoff spread, and the powdered sugar together on high speed until smooth and fluffy. Spread the flat side of half of the cooled cakes with the buttercream, then sandwich with another cake, flat side on buttercream. (Or use a piping bag and large star tip to pipe the on frosting.)