Preheat oven to 400 ℉ and prepare a 9x9 inch baking dish with baking spray or parchment paper.
In a mixing bowl, whisk together milk, sourdough discard, eggs, and melted butter.
Add in the brown sugar and mix well.
On top of the wet ingredients add cornmeal, flour, salt, and baking powder.
Mix until combined, all flour pockets should be gone. Don't overmix.
Transfer to baking pan and smooth out. Bake for 20-25 minutes until inserted toothpick comes out clean.
Notes
Note: If doubling the recipe, make sure to bake in a 9x13 inch pan, and bake at 375℉ for 50-55 minutes, making sure to test for doneness with an inserted toothpick and making sure it comes out clean. Store at room temperature for up to 3 days or freeze for up to 3 months.