Preheat oven to 350 F and arrange rack in center. Line 1 (12 cup) muffin pan with baking cups; set aside. Whisk together flour, baking powder and salt in a bowl; set aside. Beat together butter and granulated sugar in a large bowl on high speed until light and fluffy, about 2 minutes. Add eggs and extract; beat until combined well, about 2 minutes. Alternately add flour mixture and coconut milk, beginning and ending with flour mixture, beating until just combined.
Divide batter among baking cups and bake until cupcakes spring back when lightly touched, 18 to 20 minutes. Cool 10 minutes, remove cupcakes and cool completely on rack.
Holding a small knife at ab angle, cut a 1 1/2 inch round in the top of each cupcake, forming a shallow cone shaped opening. Remove tops and fill each cupcake with 2 tablespoons custard; re-cover. Dollop whipped cream on top of each cupcake and garnish with toasted coconut flakes.
Coconut Custard Directions:
Whisk together cornstarch, sugar and salt in a medium saucepan. Add milk, coconut milk and yolks; whisk until combined well. Bring to a boil over moderately high heat, stirring constantly; immediately remove from heat. Add butter and stir until melted and combined well. Transfer to a bowl set over ice and cold water; let cool completely, stirring occasionally.