1. Heat oven to 425 degrees. Generously butter an 8-by-8-by-2-inch baking pan, and set aside.

2. In a medium bowl, combine cornmeal, flour, sugar, baking powder, and salt. In a small bowl, whisk together the milk and egg. Add milk mixture to flour mixture. Add the melted butter, and whisk to just combine.

3. Pour mixture into pan; bake until golden brown and firm to the touch, 18 to 20 minutes. Transfer to a wire rack to cool completely. Let stand overnight, uncovered.