Add the vegetable oil to a 10-inch cast iron skillet and use a piece of parchment or waxed paper to evenly coat the inside of the skillet. Place the skillet in the oven while it preheats. Preheat oven to 425°F.
1 tablespoon vegetable oil
In a large bowl, whisk together the cornmeal, flour, baking powder, baking soda, and salt.
1 ¼ cups cornmeal, ¾ cup all-purpose flour, 1 tablespoon baking powder, ½ teaspoon baking soda, 1 teaspoon fine sea salt
In a medium bowl or large measuring cup, whisk together the buttermilk, melted butter, honey, and eggs. Whisk in the mashed sweet potato until well combined.
1 cup buttermilk, ¼ cup unsalted butter, ¼ cup honey, 2 large eggs, 1 cup cooked and mashed sweet potato
Add the wet ingredients to the dry ingredients and stir until just combined.
Spread the batter into the preheated skillet. Bake for 18-23 minutes, or until the top is golden brown and a toothpick inserted in the center comes out clean.
Serve warm with butter and additional honey as desired.
Notes
Ingredients
If you prefer a slightly sweeter cornbread, you can add up to 2 tablespoons granulated or light brown sugar with the dry ingredients.
Cook one large or two small sweet potatoes to get 1 cup of mashed sweet potato. To cook the potatoes:
Poke the whole sweet potatoes all over with a fork or paring knife. Microwave on high until cooked through (time will depend on the size of the potatoes—small potatoes usually need 5-7 minutes, while large potatoes may need 10+ minutes). Let cool slightly, then scoop out the sweet potato flesh and mash with a fork or potato masher.
Poke the whole sweet potatoes all over with a fork or paring knife. Wrap in foil and bake at 425°F for 40-50 minutes, or until cooked through. Let cool slightly, then scoop out the flesh and mash with a fork or potato masher
Equipment
If you don't have a cast-iron skillet, you can bake the cornbread in a greased 9-inch cake pan. You do not need to preheat the pan in the oven before adding the batter.