Cozy Homemade Banana Pudding Cookies

Preheat oven to 350°F. Open pudding mix and set aside 2–3 tbsp for the buttercream. Whisk together flour, baking soda, salt, and pudding mix. In a separate bowl, whisk melted butter and sugars until smooth. Mix in banana, egg yolk, and vanilla. Add dry ingredients to wet and mix until just combined. Fold in vanilla wafers. Scoop into 2–3 tbsp portions and bake for 10–12 minutes, until edges are set and centers are still soft. Cool on the baking sheet for 5 minutes, then transfer to a rack. For the buttercream, beat butter until fluffy, then beat in powdered sugar and pudding mix. Add milk as needed and a pinch of salt. Frost cooled cookies and top with a vanilla wafer and sliced banana just before serving.