Cheesy Baked Tennessee Onions are a Southern staple that transforms simple sweet onions into a rich, bubbling casserole of melted cheese and savory spices. This easy-to-prepare dish is the ultimate comfort food, serving as the perfect companion to grilled meats or a decadent topping for your favorite burger.
Why You Will Love This Recipe
This simple, cheesy casserole is everything you want in a side dish: it is rich, savory, and incredibly easy to throw together. Whether you are hosting a holiday meal or bringing something special to a neighborhood potluck, Tennessee onions always steal the show. The onions become perfectly caramelized and gooey, offering a mix of savory goodness that is impossible to resist.
Ingredients
- 2 1/2 pounds Vidalia onions (or Walla Walla/Maui onions), cut into 1/2-inch slices
- 1/4 cup salted butter, cut into small pieces
- 4 ounces mild cheddar cheese, freshly shredded
- 4 ounces smoked Gouda, freshly shredded
- 1 teaspoon garlic salt
- 1 teaspoon dried thyme
- 1 teaspoon dried parsley
- 1/2 teaspoon dried oregano
- 1/2 teaspoon dry mustard
- 1/4 teaspoon cayenne pepper (adjust to taste)
- Cooking spray for the baking dish
Step-by-Step Instructions
- Prepare a Baking Dish: Preheat your oven to 350°F. Coat a 13- x 9-inch baking dish with cooking spray. In a small shallow bowl, combine the thyme, dried parsley, garlic salt, dried oregano, cayenne, and dry mustard, and stir until well blended.
- Layer the Ingredients: Arrange half of the sliced onions evenly in the bottom of the prepared baking dish. Sprinkle the onions with half of the combined aromatic spice mixture.
- Repeat the Layer: Place half of the butter pieces over the onion layer, followed by half of the shredded cheddar and smoked Gouda. Repeat the process with the remaining onion slices, spices, butter, and cheeses to create a second layer.
- Cover and Bake: Cover the dish tightly with aluminum foil. Bake in the preheated oven for about 40 minutes, or until the onions have softened and the sides are bubbling.
- Uncover and Bronze: Remove the foil from the dish. Continue baking for another 15 to 30 minutes, depending on your oven, until the cheese on top is golden brown and crispy.
- Serve: Remove from the oven and serve warm while the cheese is gooey and the onions are tender.
Expert Tips / Pro Tips
To ensure the best results, use a mandoline slicer to get uniform 1/2-inch-thick slices, which helps the onions cook evenly. For the best melt, avoid pre-shredded bagged cheese; instead, buy whole blocks of cheddar and Gouda and shred them yourself. If you want an extra crunch, you can sprinkle a handful of breadcrumbs over the cheese during the last 15 minutes of baking. For better flavor development, you can prep the dish up to 24 hours in advance and keep it covered in the refrigerator until you are ready to bake.
Variations & Substitutions
While Vidalia onions are the classic choice, you can substitute them with other sweet varieties like Walla Walla or Maui onions. If you prefer a different cheese profile, a combination of Mozzarella, Sharp Cheddar, and Parmesan works beautifully. For those who enjoy more heat, increase the cayenne pepper to 1/2 teaspoon or add a few red pepper flakes. If you need to omit the heat entirely, simply leave out the cayenne pepper.
Serving Suggestions
These onions are a fantastic topping for juicy burgers or Shaved Beef French Dip Sandwiches. They also pair perfectly with grilled meats such as barbecued chicken drumsticks, beef tips in mushroom sauce, or Carolina pulled pork. For drink pairings, consider a pale ale or a crisp Chardonnay. If you prefer cocktails, a classic Moscow mule or a gin and tonic complements the savory and sweet notes of the dish quite well.
Storage, Freezing & Reheating
Leftover Tennessee onions should be stored in an airtight container in the refrigerator for up to 3 days. To reheat, place them in an oven-safe dish at 350°F until warmed through and the cheese is bubbly again. Freezing is not recommended for this recipe, as the texture of the onions becomes mushy and the cheese can separate upon thawing and reheating.
Nutrition Information
| Nutrient | Amount per Serving |
|---|---|
| Calories | 165 kcal |
| Carbohydrates | 9 g |
| Protein | 6 g |
| Fat | 12 g |
| Saturated Fat | 7 g |
| Cholesterol | 36 mg |
| Sodium | 445 mg |
| Fiber | 1 g |
| Sugar | 6 g |
Note: Nutrition information is an approximation based on 10 servings.
FAQ
What kind of onions work best for Tennessee onions?
Sweet onions are the best choice for this recipe. Look for varieties like Vidalia, Walla Walla, or Maui. These onions have a higher sugar content and a milder flavor, which allows them to caramelize beautifully without being overpowering.
How do I keep Tennessee onions from getting watery when baked?
Onions naturally release moisture as they cook. To minimize excess liquid, ensure you are using large, firm onions and do not overcook them in the first stage. Baking uncovered for the final 15-30 minutes also helps some of the moisture evaporate while crisping up the cheese.
Can I make Tennessee onions ahead of time?
Yes! You can assemble the entire dish, cover it, and refrigerate it for up to 24 hours before baking. When you are ready to cook, let the dish sit at room temperature for about an hour so it heats evenly in the oven.
Cheesy Baked Tennessee Onions
Ingredients
Method
- Preheat oven to 350°F. Coat a 9×13-inch baking dish with cooking spray.
- In a shallow bowl, combine the thyme, dried parsley, garlic salt, dried oregano, cayenne, and dry mustard.
- Arrange half of the sliced onions evenly in the prepared baking dish to cover the base.
- Sprinkle with half of the combined spices, then arrange half of the butter pieces and half of the shredded cheeses on top.
- Repeat the process with the remaining onions, spices, butter, and cheeses to create a second layer.
- Cover the dish with aluminum foil and bake for 40 minutes until the onions are soft and the sides are bubbly.
- Remove the foil and continue baking for 15 to 30 minutes until the top is golden brown and crispy.