Preheat oven to 350 degrees. Sift the sugar, flour and baking powder. In a separate bowl, beat the egg with the milk and salt. Combine the flour and egg mixtures and place in an 8-inch round, 2-inch deep, baking dish. Sprinkle with the cinnamon sugar and drizzle the melted butter over the top. Bake for 1/2 hour or unitl done.