1. Preheat oven to 350 degrees. Line 18 standard muffin cups with paper or foil liners. In a large bowl, whisk together flour, baking powder, and salt. In a separate bowl, beat butter with sugar on medium speed until light and fluffy. Add eggs, one at a time, beating well after each addition. Beat in vanilla. Reduce speed to low and add flour mixture in 2 batches, alternating with milk. Beat in melted chocolate.

2. Divide batter evenly among muffin cups, filling each about two-thirds full. Bake until a tester inserted in centers comes out clean, 18 to 20 minutes. Let cool in pan on a wire rack 5 minutes, then remove cupcakes and let cool completely on rack. (Cupcakes can be made ahead up to this point and stored in an airtight container at room temperature up to 2 days.)

3. Transfer pudding to a pastry bag fitted with a 1/4-inch plain round tip. Insert tip in top of a cupcake and squeeze until cupcake begins to mound. Repeat with remaining cupcakes. Refrigerate until cold, about 30 minutes and up to 1 day. Spoon about 2 teaspoons ganache over top of each cupcake; top with chocolate curls. Refrigerate at least 15 minutes before serving.