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If you've ever struggled to choose between mozzarella sticks and onion rings, you know how difficult ordering bar food can be. But what if there was an appetizer that combined them both, so you'd never have to face such a cruel and impossible decision again? Under the working theory that nothing can go wrong when I combine my favorite bar foods, I decided to put those two together to make one ring that rules them all: Mozzarella-Stuffed Crispy Baked Onion Rings.
When I decided to embark on my onion ring journey, I decided that there would be a few absolute "musts" for my recipe. The perfect onion ring must...
- ...be thick.
- ...have a good, strong onion flavor.
- ...be crunchy.
- ...not be greasy.
- ...have an intact coating that does not slide off easily.
- ...and contain a fully cooked-through onion.
Bonus points are awarded for making the process more accessible for the home cook.
The only criteria for the mozzarella mix-in was that the onion rings had to have a stringy, melted cheese center that didn't completely ooze out.
It seems simple, but those of us who have ever tried to bake anything that's stuffed with cheese know that nine times out of ten, you wind up with a dairy massacre. There would be no cheesy carnage with these though. Not on my watch.
To start, I decided to take a tip from Josh's Baked Jalapeño Popper recipe. In it, he gets the coating to stick to the slick surface of the jalapeños by dipping them in buttermilk first, followed by flour. I decided to increase the buttermilk time from a dip to an extended soak when adapting it for the onions. Aside from giving a consistent, clinging coating, the buttermilk's enzymes help soften the onions and draw out some of their harsh bite.
Because I wanted to keep the cheese secure and I wanted a noticeable onion flavor and texture, I decided to double up my rings. I took the largest rings and matched them with slices that were about 1/2" smaller in diameter. I placed the smaller rings inside of the bigger rings, and then I tucked mozzarella string cheese between them. It was easier than I expected to get a snug fit that held the onions together, and then I went on to dipping and baking.
But even with all my preparations, I still had a couple sad dairy mishaps on my first two attempts. I found that the best way to prevent any cheese leaks was to freeze the cheese first, then set it out for 5 minutes or so—just long enough to make it pliable but still very cold. Due to the low moisture content of string cheese, the texture isn't harmed from freezing. Instead, the freezing allows the exterior of the onion ring to bake without overcooking the cheese inside and causing it to spill out of any gaps in the coating.
To help avoid those dangerous gaps, I wanted to make sure the coating was extra thick. To do that, I first took the buttermilk-soaked onions and dunked them in whole-wheat flour. Then I dipped them in egg, back in the flour, then egg again, and lastly in a mixture of cornmeal, Corn Chex, panko, and—you guessed it—more flour.
Why so much flour, and why whole wheat? The whole wheat flour allows for a dense coating by filling in any gaps between the larger, airier flakes of panko and Corn Chex. Whole wheat also adds to the subtle nuttiness of cornmeal, making for a more flavorful coating that doesn't require a ton of seasonings.
The double-onion, extra coated, mozzarella-stuffed onion rings took a bit of time to get right, but after that first batch came out of the oven so crunchy, intact, and tender inside, I knew it was worth it. However, if there was ever a moment of doubt, it was completely obliterated when my family destroyed any trace of the rings as soon as I'd served them. I can't say I blame my family though. How can anyone resist going wild when there are cheese-stuffed onion rings in front of them?
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