Tennessee Onions are an old fashioned Southern cheesy onion casserole that is an excellent side dish or a condiment for burgers and sandwiches. Tender onion slices and pools of melted cheese are seasoned generously and baked with a good amount of butter to create a creamy, cheesy onion casserole.

Onions are the star in a lot of popular recipes such as French Onion Soup, Caramelized Onion Dip, Onion Rings and Balsamic Onion Burgers.

The classic “Tennessee” onions recipe calls for using Georgia grown Vidalia onions. Vidalia onions get their natural sweetness from the unique soil of the Vidalia, Georgia region. They’re mild onions and they do still have a slight bite to them when raw, but it’s more of a gentle tang instead of a sharp burn.

So why isn’t this recipe called, “Georgia” onions? No one is really sure. The dish has origins in the Appalachian region (which runs through Tennessee). It has been a modern southern favorite to make for potlucks, cookouts, or church suppers.

ingredients displayed for making tennessee onions

Ingredients Needed:

Sweet Onions: The classic recipe calls for using sweet Vidalia onions. You can substitute any sweet onion: Walla Walla, Texas Sweet or Maui.
Butter: Use salted butter for the best flavor. It’s the base of the sauce.
Brown Sugar: A little sweetness added in helps to caramelize the onions.
Spices: Garlic powder, smoked paprika, cayenne powder and salt and pepper.
Cheese: I think the best combination of cheeses to use for making Tennessee onions is Gruyere and sharp cheddar cheese. More suggestions are included in the recipe tips below.

How to make Tennessee Onions:

The complete, printable recipe is at the end of this post. Here’s a brief overview.

Preheat the oven, and spray a baking dish with nonstick spray.
Add the onions to a bowl. Drizzle with melted butter, and toss.
Combine the sugar with the spices. Sprinkle over the onions, and toss again.
Add the two cheeses to a bowl and toss to combine.

Add half of the onions to the dish. Sprinkle half the cheese on top. Add the rest of the onions, and top those with the rest of the cheese. Dot the butter all over the top. Cover with foil and bake for 45 minutes. Remove the foil, and bake for an additional 15 to 20 minutes, until the onions are soft and the cheese is bubbly.

Recipe Tips

Be sure to slice the onions evenly into rings that are 1/8th-inch to 1/4-inch wide. Separate the rings so they’ll cook evenly in the casserole dish.
You can experiment with using different cheeses. Just be sure to use a couple of varieties for the best flavor. Good melting cheeses to use for making Tennessee onions are Fontina, Gouda, Provolone and Monterey Jack.
Suggested additions: cooked bacon, smashed garlic, sprigs of fresh herbs such as thyme or rosemary and breadcrumbs sprinkled on top.
Try using different seasonings such as Cajun seasoning or Old Bay seasoning.
Don’t let the buttery sauce on the bottom of the baking dish go to waste. Use a hunk of bread to soak up the sauce and eat!
Make ahead tip: Tennessee onions can be prepared one day before serving and stored in the refrigerator.
Storing leftovers: Keep any leftovers in an airtight container, and refrigerate for up to 3 days. Reheat at 350 degrees F for 10 minutes, until hot and bubbly again. Don’t freeze Tennessee Onions.

What Would You Use Tennessee Onions For?

These buttery soft melt-in-your-mouth onions baked with melted cheese are a great side dish for fried chicken, steak, roast beef or meatloaf. They’re also really fantastic when used as a condiment to add to a burger, grilled cheese or Philly cheese steak sandwich.

What We Love About This Recipe:

They are a low effort recipe, but they’re very flavorful.
The recipe calls for using simple ingredients.
Tennessee Onions are always a big hit at a family gathering, potluck party or church supper!