This is a skillet cornbread built around two pouches of Betty Crocker cornbread mix, a full cup each of Parmesan and mozzarella, fresh thyme and parsley, and a layer of butter-softened sweet onion rings that end up on top once you flip it out. The honest reason to make it: the flip gives you a genuinely impressive presentation with almost no extra effort, and the whole thing is done in an hour.
Ingredient notes
- Betty Crocker cornbread muffin mix: Two standard 6.5 oz pouches. Any similar boxed cornbread mix works — Jiffy is the most common swap and costs less. Just use the same total volume.
- Sweet onion: Vidalia is ideal, but any large mild onion does the job. Yellow onions work fine; they just have a sharper bite before cooking. Avoid red onion here — it bleeds color into the batter.
- Parmesan: Pre-shredded is fine. Grana Padano or Pecorino Romano are solid substitutes if that’s what’s in your fridge. Skip the powdery stuff in the green can — it won’t melt the same way.
- Mozzarella: Low-moisture, part-skim shredded mozzarella is what you want. Fresh mozzarella has too much water and will make the batter soggy. Monterey Jack melts just as well if mozzarella isn’t on hand.
- Fresh herbs: Dried thyme works in a pinch — use 2 teaspoons instead of 2 tablespoons of fresh. Dried parsley is a weaker substitute but acceptable. Skip the garnish of extra fresh herbs on top — not worth the extra dish.
The short version of why this works
Two things actually matter here. First, the cast iron skillet retains and distributes heat evenly, which is what gives the edges and bottom a firm, golden crust while the inside stays moist — a regular cake pan won’t do that as reliably. Second, briefly cooking the onion rings in butter on the stovetop before the batter goes in softens them just enough that they won’t steam and make the cornbread wet during baking. That short stovetop step is the difference between a soggy bottom and a clean flip with intact, golden onion rings sitting on top.
If something goes sideways
- The onion rings stuck to the skillet: This usually means the butter wasn’t coating the whole pan bottom, or the skillet wasn’t hot enough before the onions went in. Next time, swirl the butter to coat fully before arranging the rings. If it happens mid-flip, use a thin spatula to gently coax the stuck pieces back into place on top — it still tastes the same.
- The center is set but the edges are pulling away and look dry: Your oven runs hot. Pull it at the lower end of the bake window (28 minutes) and check with a toothpick rather than going by color alone.
- The cornbread crumbled when flipped: It needed more time to rest. Ten minutes in the skillet is the minimum; if your kitchen is cold, give it 12 to 15. The crumb needs to firm up before it can hold together through the inversion.
- The batter looks very thick going into the pan: That’s normal with two pouches of mix plus two cups of cheese. Spread it gently with a spatula — don’t press down hard or you’ll compress the onion rings underneath.
- The cheese browned too fast on top before the center was done: Tent the skillet loosely with foil after the first 20 minutes and continue baking. This slows the surface browning without affecting the interior.
Keeping and reheating
Leftovers keep well wrapped tightly or in an airtight container in the fridge for up to 3 days. To reheat, place wedges cut-side down in a dry skillet over medium-low heat for 3 to 4 minutes — this brings back some of the crust without drying out the crumb. The microwave works if you’re in a hurry (about 45 seconds per wedge), but the edges go soft. For longer storage, freeze individual wedges wrapped in plastic and then foil for up to 2 months; thaw overnight in the fridge before reheating in the skillet.
Cheesy Onion Cornbread
Ingredients
- 4 tablespoons butter
- 1 large sweet onion
- ¼ teaspoon fine salt
- 2 pouches cornbread & muffin mix Betty Crocker™
- 2 large eggs
- 1 cup Parmesan cheese shredded
- 1 cup mozzarella cheese shredded
- ¼ cup parsley chopped ; fresh Italian (flat-leaf) parsley
- 2 tablespoons thyme leaves fresh ; chopped
- 1 cup milk
Instructions
- Preheat the oven to 350°F / 175°C (160°C fan-forced). Position a rack in the centre of the oven. Cut onion into 5 (1/2-inch thick) rings; keep the rings in place.
- In a 10-inch (25cm) oven-safe cast iron skillet, melt the butter over medium-low heat. Arrange the onion rings in a single layer in the melted butter. Sprinkle with salt and cook for 3 to 4 minutes until the onions begin to soften. Using a wide spatula, gently flip the onion rings, keeping them intact as much as possible. Remove the skillet from the heat.
- In a large bowl, combine both pouches of cornbread mix, the eggs, and the milk. Stir until just combined — a few small lumps are fine. Fold in the Parmesan, mozzarella, parsley, and thyme until evenly distributed.
- Pour the batter evenly over the onions in the skillet, spreading gently with a spatula to the edges. Bake at 350°F / 175°C for 28 to 32 minutes, or until the top is golden brown and a toothpick inserted into the centre comes out clean.
- Run a butter knife around the edge of the skillet to loosen the cornbread. Let it cool in the skillet for 10 minutes.
- Place a large serving plate or cutting board over the skillet. Wearing oven mitts, carefully and quickly invert the skillet onto the plate so the onion layer is on top. Cut into 8 wedges and serve warm.
Nutrition
FAQ
Can I use a regular oven-safe skillet instead of cast iron?
Yes, any oven-safe skillet that’s at least 10 inches wide will work. Cast iron gives you a better crust on the bottom and edges because of how it holds heat, but a stainless steel or carbon steel pan will still produce a good result — just watch the bake time, as thinner pans can cook faster.
Do I have to flip it, or can I just serve it straight from the skillet?
You can absolutely serve it straight from the skillet. The flip is purely for presentation — the onion rings end up on top instead of hidden underneath. If you skip the flip, just cut and scoop wedges directly from the pan.
Can I make this without the fresh herbs if I don’t have any?
Yes. Use 2 teaspoons of dried thyme as a substitute for the fresh, and either 1 tablespoon of dried parsley or just leave it out entirely. The cheese and onion carry the flavor well on their own.
Can I prep this ahead of time?
You can mix the dry batter ingredients and shred the cheese a few hours ahead, but don’t combine the wet and dry ingredients until you’re ready to bake — the leavening in the cornbread mix starts working once it hits liquid. The onions can be sliced and refrigerated a day in advance.
My skillet is 12 inches, not 10. Will that change anything?
It will spread the batter thinner, so reduce the bake time by about 5 minutes and start checking at the 23-minute mark. The cornbread will be slightly flatter but will still work. The onion layer may also spread out more, so try to keep the rings toward the center of the pan.
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