Name: Mounds Whoopie Pies
Yield: 7
Ingredients: Cakes; 1 stick (1/2 cup; 4 oz) butter, softened; 7 oz brown sugar; 1 tsp pure vanilla extract; 1 large egg; 2-1/3 cups all-purpose flour or 300g gluten-free all-purpose blend; 1-1/4 tsp baking soda; Pinch of kosher or fine sea salt; 1 cup low fat buttermilk; Filling; 3 tbsp butter, at room temperature; 2 cups (16 oz) powdered sugar, or as needed; Pinch kosher or fine sea salt; Milk, as needed; Toppings; 7 oz dark chocolate, finely chopped; 1 cup shredded sweetened coconut