Tennessee Onions are an irresistibly simple southern side dish that transforms humble sweet onions into a bubbling, golden pan of cheesy, savory goodness. With layers of tender onions crowned by a gooey blanket of three kinds of cheese, each bite delivers deep, comforting flavors and that unforgettable oven-baked aroma. Whether you’re serving these alongside smoky barbecue, roasted meats, or making them the star of your dinner table, Tennessee Onions never fail to gather folks around for “just one more scoop.”

Ingredients You’ll Need

You’ll be amazed at how just a handful of everyday ingredients come together to create a side dish that steals the show. Each component in Tennessee Onions brings its own signature taste and texture, working together to make this casserole rich, creamy, and utterly crave-worthy.

3 large sweet onions (like Vidalia): Sweet onions are the backbone here, their natural sugars mellowing and deepening as they bake.
2 tablespoons unsalted butter: Adds richness and encourages the onions to soften and caramelize at the edges.
1 teaspoon garlic powder: Boosts flavor with a gentle, savory kick that dances with the cheesy topping.
1/2 teaspoon salt: Essential for balancing the sweetness and bringing out the savory notes.
1/2 teaspoon black pepper: A little heat to perk everything up without getting in the way.
1/2 teaspoon dried thyme (optional): Offers herbaceous depth that’s subtle but adds a great layer of flavor.
1 cup shredded mozzarella cheese: Melty and stretchy, mozzarella helps give that luscious cheesy pull.
1 cup shredded cheddar cheese: Cheddar brings tanginess and bold color to the topping.
1/2 cup grated Parmesan cheese: Parmesan rounds things out with its salty, nutty bite.
Fresh parsley for garnish (optional): A sprinkle of green brings a pop of freshness and color at the end.

How to Make Tennessee Onions

Step 1: Prep the Basics

Preheat your oven to 375°F (190°C) and lightly grease a 9×13-inch baking dish. This ensures your Tennessee Onions won’t stick and makes for a super easy clean-up later. Gathering your equipment first means you can savor every aromatic moment as the dish comes together.

Step 2: Slice the Onions

Thinly slice your sweet onions, letting each ribbon of onion melt tenderly into the next when baked. A sharp knife or mandoline makes quick work of it, and the thinner the slice, the more evenly the onions will cook and soak up all those buttery, cheesy flavors.

Step 3: Arrange and Season

Spread your sliced onions evenly in the prepared baking dish. Dot the surface with pieces of butter, then sprinkle the garlic powder, salt, black pepper, and thyme (if using) over the top. Give everything a light toss, just enough to coat the onions in the seasonings and butter.

Step 4: Pile on the Cheese

Here’s where Tennessee Onions become truly irresistible. Layer your mozzarella, cheddar, and Parmesan cheeses evenly over the top. This trio of gooey, golden cheeses is the secret to that unforgettable bubbly, decadent topping.

Step 5: Bake to Golden Perfection

Cover the dish with foil and bake for 25 minutes so the onions become tender and the flavors meld together. After that, remove the foil and bake for another 15 to 20 minutes uncovered, letting the cheese turn gloriously golden and bubbling. The smell alone will have you hovering by the oven door in anticipation!

Step 6: Garnish and Serve

Sprinkle fresh parsley over your finished Tennessee Onions for a bright pop of color. Serve them piping hot, scooping generous helpings onto plates for that perfect cheesy stretch. Try not to snag all the best caramelized edges for yourself!

How to Serve Tennessee Onions

Garnishes

A finishing sprinkle of fresh parsley gives Tennessee Onions a gorgeous contrast, making them pop with color and a hint of herbal freshness. For extra flair, some folks add a sprinkle of chives or even a pinch of smoky paprika before serving.

Side Dishes

Tennessee Onions are versatile partners for hearty fare – think alongside barbecued chicken, juicy steaks, pork chops, or even a rich vegetarian main. They’re also right at home at a holiday table among stuffing, mashed potatoes, and roasted veggies.

Creative Ways to Present

Try spooning Tennessee Onions into individual ramekins for a dinner party-worthy side. For summer cookouts, serve them right from a cast iron skillet to keep things rustic. You can even ladle luscious scoops over toasted bread or into baked potatoes for a decadent twist.

Make Ahead and Storage

Storing Leftovers

If you have any Tennessee Onions left (they go fast!), let them cool to room temperature and store in an airtight container in the fridge for up to 3 days. The flavors continue to meld and deepen, making leftovers just as delightful as day one.

Freezing

Tennessee Onions can be frozen for up to three months. Allow the dish to cool completely, portion it into freezer-safe containers, and be sure to label. The texture may soften a bit upon reheating, but the flavor remains comforting and delicious.

Reheating

To reheat, place leftovers in an oven-safe dish, cover with foil, and warm at 350°F for about 15 minutes, or until hot throughout. You can also microwave single servings for 1–2 minutes; add a little extra cheese on top if you want to revive that gooey magic!

FAQs

Can I use a different type Side Dish

Absolutely! While sweet onions like Vidalia are traditional, you can use yellow or white onions if that’s what you have. Just know that the dish may have a bit more of that classic onion sharpness without the natural sweetness Vidalias provide.

What cheeses work best for Tennessee Onions if I want to experiment?

Feel free to play around with the cheese combo! Monterey Jack, Gruyère, or smoked gouda add fun variety. Just be sure to keep the proportions similar so the cheesy topping melts evenly and stays decadent.

Is it possible to make Tennessee Onions ahead for a party?

Yes! You can assemble the entire dish a day in advance, cover tightly, and refrigerate. Simply add a few extra minutes to the baking time straight from the fridge, and finish uncovered for golden perfection.

Can you make Tennessee Onions without butter for a lighter version?

If you’re avoiding butter, substitute with olive oil or a plant-based buttery spread. The flavors will shift ever-so-slightly, but your Tennessee Onions will still be creamy, rich, and crowd-pleasing.

What’s one secret tip for getting the best flavor?

For layers of deep flavor, try caramelizing the onions lightly on the stovetop before baking. It’s an extra step, but the sweet, rich flavor payoff is totally worth it!

Final Thoughts

No matter the occasion or the company, Tennessee Onions guarantee smiles and second helpings. They’re proof that simple ingredients, when given a little love and a whole lot of cheese, can steal the spotlight at any meal. Go ahead and give them a try – you might just add a new favorite to your table!

Tennessee Onions Recipe

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4.7 from 10 reviews

Author: admin
Total Time: 50 minutes
Yield: 6 servings 1x
Diet: Vegetarian

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Description

Tennessee Onions is a delicious and cheesy side dish that features thinly sliced sweet onions baked to perfection with a blend of three cheeses. This savory recipe is easy to prepare and makes a great addition to any meal.

Ingredients

Scale

Ingredients:

3 large sweet onions (like Vidalia), thinly sliced
2 tablespoons unsalted butter
1 teaspoon garlic powder
1/2 teaspoon salt
1/2 teaspoon black pepper
1/2 teaspoon dried thyme (optional)
1 cup shredded mozzarella cheese
1 cup shredded cheddar cheese
1/2 cup grated Parmesan cheese
fresh parsley for garnish (optional)

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Instructions

Preheat oven: Preheat oven to 375°F (190°C). Lightly grease a 9×13-inch baking dish.
Prepare onions: Spread the sliced onions evenly in the dish. Dot the butter over the onions and sprinkle with garlic powder, salt, pepper, and thyme if using. Toss lightly to coat.
Add cheese: Sprinkle all three cheeses evenly over the top.
Bake: Cover with foil and bake for 25 minutes. Remove the foil and bake uncovered for an additional 15–20 minutes, or until the onions are tender and the cheese is golden and bubbly.
Garnish: Garnish with fresh parsley if desired.