Preheat the oven to 400°F
Grease an 8-inch square baking pan or cast-iron skillet
In a large bowl, whisk together 1 cup cornmeal, 1 cup all-purpose flour, 1 tablespoon baking powder, 1/2 teaspoon salt, and 2 to 4 tablespoons sugar if desired
In a separate bowl, whisk together 1 cup milk, 1 large egg, and 1/4 cup melted butter or oil
Pour the wet ingredients into the dry ingredients
Stir until just combined
Pour the batter into the prepared pan
Bake for 20 to 25 minutes, until golden brown and a toothpick inserted in the center comes out clean
Let cool for a few minutes before slicing
Serve warm