Stir flour and confectioners sugar in a medium mixing bowl. Add milk, eggs, 3 tablespoons melted butter, vanilla and salt, wisk together until smooth. Heat and lightly grease a griddle, add 2 tablespoons batter and smooth out thinly, cook until lightly browned, turn and brown remaining side. Repeat with the balance of the batter. Cool on a wire rack.
For filling, melt butter in a large skillet, stir in brown sugar, cinnamon and nutmeg, stir in cream and heat until thickened. Split bananas lengthwise and add to the filling, heat for 2 minutes turning after one minute.
To serve, wrap a crepe' around each banana slice and place crepes on plates, Spoon sauce over crepe and top with whip cream and powdered sugar to garnish.