Preheat the oven to 400℉ . Grease a square 9x9 baking dish with baking spray or butter.
Warm buttermilk in a microwave safe container for 30 seconds. Add cornmeal to the buttermilk, stir to mix, and set aside.
In a large bowl, add the flour, sugar, baking powder, baking soda, and salt and stir to mix it together.
Add the vegetable oil and beaten eggs to the buttermilk mixture. Mix well.
Next, add the buttermilk and egg mixture to the flour mixture and mix just until combined. Some lumps are okay.
Bake for 20-25 minutes until a toothpick comes out clean when poked in the center.
Notes
To make cornbread muffins:Grease a muffin tin or line with cupcake liners. Use a large cookie or ice cream scoop to divide the mixture between the prepared muffin tins. Bake for 12-15 minutes until a toothpick comes out clean when poked in the center of the muffin.Makes 12 muffins.Buttermilk substituteYou can swap out buttermilk for regular milk by adding 1 Tablespoon of white vinegar or lemon juice to a liquid measuring cup. Add enough milk to the white vinegar to make 1 cup. Stir and let sit for a couple minutes to let the vinegar react with the milk.
If you have no vinegar, then use regular milk and increase the baking powder to 1 Tablespoon.