Name: Cheesy Tennessee Onions Recipe
Prep time: 15 min
Cook time: 1 h 5 min
Total time: 1 h 20 min
Cuisine: American Southern
Ingredients: 2 1/2 lbs sweet onions, sliced into ¼ inch rings; 1 teaspoon dried parsley; 1 teaspoon dried oregano; 1 teaspoon Cajun seasoning; 1 teaspoon garlic powder; ½ teaspoon kosher salt; ¼ teaspoon ground black pepper; ¼ cup unsalted butter, sliced into pats; 1 cup sharp cheddar cheese, shredded; 1 cup mozzarella cheese, shredded; ⅓ cup parmesan cheese, grated or shredded

Print Recipe· 3.9 from 9 reviews

If you crave the cozy feeling of comfort food with a delightful twist, you are going to love this Cheesy Tennessee Onions Recipe. Imagine layers of tender, sweet onions perfectly seasoned with a blend of herbs and spices, all smothered in a rich, bubbly crown of cheddar, mozzarella, and parmesan cheeses. This dish offers a warm, melty texture and savory taste that brings a Southern charm right to your table. Whether you’re serving it as a side or a main, the Cheesy Tennessee Onions Recipe is irresistibly tasty and unbelievably satisfying.

Ingredients You’ll Need

The image shows a top view of cooking ingredients neatly arranged on a white marbled textured surface. In the center is a bowl filled with several white round onion slices stacked evenly. Surrounding it are small white bowls containing three different types of shredded cheese: a bowl of light yellow cheese at the top left, a bowl of white cheese to the right middle, and an orange shredded cheese bowl at the bottom right. Above the onion bowl is a white square plate holding four piles of different colored spices: green, red, beige, and dark green. To the right of the onion bowl is a stick of unsalted butter in its wrapper. At the bottom left corner are two small silver salt and pepper shakers. The whole arrangement is clean and simple, with clear separation between each ingredient. photo taken with an iphone --ar 4:5 --v 7

Every ingredient in this recipe plays a critical role in striking the perfect balance of flavor, texture, and richness. These essentials are simple but far from basic, working together to make this dish shine with authentic Tennessee-style comfort.

2 1/2 lbs sweet onions: Sliced into ¼ inch rings, these are the heart of the dish with their natural sweetness and tender bite when baked.
1 teaspoon dried parsley: Adds a subtle earthiness and a pop of green color to brighten the dish.
1 teaspoon dried oregano: Brings a hint of herbal depth that complements the sweet onions.
1 teaspoon Cajun seasoning: Provides a mild spicy kick that livens up the flavor profile without overwhelming it.
1 teaspoon garlic powder: Boosts the savory notes and adds a warm aroma throughout the dish.
½ teaspoon kosher salt: Enhances all the flavors, making every bite sing with balance.
¼ teaspoon ground black pepper: Gives a gentle peppery heat that rounds out the spices.
¼ cup unsalted butter: Sliced into pats, this melts into the onions to deliver a luscious richness.
1 cup sharp cheddar cheese: Shredded for melting, it adds tanginess and a beautiful golden color to the top.
1 cup mozzarella cheese: Its creamy meltiness ensures the perfect gooey texture.
⅓ cup parmesan cheese: Grated, it contributes that signature umami punch and a slightly crispy top layer.

How to Make Cheesy Tennessee Onions Recipe

Step 1: Prepare and Preheat

Start by preheating your oven to 350 degrees Fahrenheit, then give your casserole dish a light spray with cooking oil to prevent sticking. Getting your oven and dish ready sets you up for perfectly cooked onions and cheese.

Step 2: Arrange the Onion Rings

Next, spread the sweet onion rings evenly across the bottom of the casserole dish. This even layer ensures every bite has that delicious onion flavor wrapped in melted cheese.

Step 3: Season and Toss

Sprinkle the dried parsley, oregano, Cajun seasoning, garlic powder, kosher salt, and black pepper right over the onions. Toss gently to coat them all with these fragrant seasonings, so the flavor is evenly distributed throughout the dish.

Step 4: Add Butter and Cheese

Dot the seasoned onions with pats of unsalted butter. This will melt slowly during baking, adding luscious moisture. Then sprinkle the shredded cheddar and mozzarella evenly over the top, finishing it off with a generous sprinkle of parmesan cheese for extra flavor and a beautiful crust.

Step 5: Bake Covered

Cover the casserole tightly with foil and bake for 50 minutes. This step lets the onions soften and the cheese slowly melt into a creamy blanket that envelops the dish in heaven.

Step 6: Finish Baking Uncovered

Remove the foil and bake for an additional 10 to 15 minutes. This time lets the cheese topping turn a warm, golden color with slightly crispy edges—truly the perfect finishing touch to this classic Cheesy Tennessee Onions Recipe.

Step 7: Rest and Serve

Allow your cheesy creation to rest for 5 to 10 minutes before serving. This brief cooling helps it set just enough to scoop up easily while keeping all the melty, cheesy goodness intact.

How to Serve Cheesy Tennessee Onions Recipe

The image shows a white baking dish with a red handle filled with thick white onion rings spread out flat. The onion rings are stacked in one layer, with some overlapping. They are lightly sprinkled with a mix of spices, visible as small specks of red, black, and green on the smooth white surface of the onions. The baking dish sits on a wooden table, but the background should appear as a white marbled texture. photo taken with an iphone --ar 4:5 --v 7

Garnishes

Fresh herbs like chopped parsley or chives make gorgeous garnishes, adding a fresh, green note that contrasts beautifully with the rich cheese. For a little color and extra flavor, sprinkle a bit of smoked paprika or crushed red pepper flakes on top just before serving.

Side Dishes

Because this casserole is rich and full of flavor, it pairs beautifully with lighter sides like a crisp green salad or steamed vegetables. Grilled meats or roasted chicken also complement the savory, melty onions perfectly for a comforting dinner.

Creative Ways to Present

Serve the Cheesy Tennessee Onions Recipe in individual ramekins for an elegant touch, or turn it into a hearty topping for toasted baguette slices as an appetizer. You could even spoon it over baked potatoes to create a crowd-pleasing loaded side dish.

Make Ahead and Storage

Storing Leftovers

Store any leftover Cheesy Tennessee Onions in an airtight container in the refrigerator. They will keep well for up to 3 days and taste just as delicious reheated when you crave that cheesy comfort again.

Freezing

This dish freezes beautifully. Simply let it cool completely, then transfer to a freezer-safe container. You can store it for up to 2 months, making it a great make-ahead option for busy weeks or unexpected guests.

Reheating

To reheat, thaw in the refrigerator overnight if frozen, and then warm in the oven at 350 degrees Fahrenheit until bubbly and heated through. You can cover with foil to avoid over-browning, removing it towards the end for a crispier cheese topping.

FAQs

Can I use other types of cheese in this recipe?

Absolutely! While sharp cheddar, mozzarella, and parmesan create a classic flavor, feel free to try gouda, fontina, or even pepper jack for a twist. Just make sure they melt well to maintain that creamy texture.

Are sweet onions essential for this dish?

Sweet onions are preferred because of their natural mildness and caramelizing quality, but you can use yellow onions in a pinch. Just keep in mind the flavor will be a bit sharper, which could change the dish’s character slightly.

Can I make this vegetarian or vegan?

The recipe is naturally vegetarian but not vegan due to the cheeses and butter. To go vegan, you could substitute with plant-based butter and dairy-free cheese alternatives, though the flavor and texture will be different from the original.

Is this dish good for meal prepping?

Definitely! The Cheesy Tennessee Onions Recipe stores and reheats well, making it a convenient and delicious meal prep choice especially if you like your lunches warm and cheesy.

How spicy is the dish with Cajun seasoning?

The Cajun seasoning adds just a gentle warmth without overpowering the sweetness of the onions and richness of the cheese. You can adjust the amount or omit it if you’re sensitive to spice, but it really enhances the overall flavor.

Final Thoughts

If you’re ready to indulge in something that feels like a big warm hug on a plate, do yourself a favor and try this Cheesy Tennessee Onions Recipe. It’s easy to prepare, packed with comforting flavors, and sure to become a favorite you reach for again and again. Trust me, once you take that first cheesy, tender bite, this dish will have a permanent place in your heart and on your table.