Preheat the oven to 350°F and set an oven rack in the middle position.
Butter and flour a 9x13-inch baking pan or spray with a nonstick cooking spray with flour, such as Baker's Joy.
In a medium bowl, whisk the eggs.
Add the milk and whisk until evenly combined. Set aside.
In a large bowl, whisk together the flour, cornmeal, sugar, baking powder, and salt.
Add the milk mixture and the melted butter to the dry ingredients and whisk until smooth.
Transfer the batter to the prepared baking pan and smooth the top.
Bake until lightly golden around the edges and set, about 30 minutes.
Cool in the pan on a wire rack until cool enough to handle, 20 to 30 minutes.