2Tbspolive oil, or other vegetable oil. Butter or bacon grease will also work, but will result in a browner top.
1largeor 2 medium Vidalia onions, peeled and sliced into 1/4 inch thick rounds. Note: you can use any type of sweet onion if you can't find Vidalias.
1tsponion salt (you can also use onion powder, just increase the salt in the recipe)
1/2tsp kosher salt
1/2cuppacked shredded cheddar cheese (you can use other types of cheese such as Gruyere.)
6Tbspunsalted butter, melted
Preheat oven to 425F
Add the oil to your skillet and heat on medium high heat. Arrange the onion slices in a single layer over the bottom of the skillet, adjusting the slices to fill as much of the surface as possible. Cook the onions, without moving them, for about 8 minutes, or until they are starting to soften and turn golden on the bottom (take care not to let it burn.) Remove from the heat.
Whisk together the cornmeal, flour, baking powder and salts in a large mixing bowl. Blend in the cheese.
In a separate bowl whisk together the eggs, buttermilk, and melted butter, mixing well to break up the eggs.
Add the wet mixture to the dry, and mix just until completely combined and there are no dry streaks left (don't over beat.) Pour the batter into the skillet, over the onions. Bake for about 27 minutes, or until a toothpick inserted in the center comes out without wet batter on it; wet crumbs are fine.
Let the skillet cool for 10 minutes, then run a blunt knife around the edges to loosen, and carefully invert onto a cooling rack. If any onions remain stuck to the pan, gently loosen them with an offset spatula and tuck them back into the top of the cornbread. Slice into wedges and serve with butter or honey.