Description
Tennessee Onions is a savory baked onion casserole layered with sweet Vidalia onions and a blend of melted cheddar, smoked Gouda, and Parmesan cheeses, all seasoned with a flavorful mix of spices and topped with butter. This comforting side dish combines the natural sweetness of onions with a rich, cheesy crust, perfect for family dinners or holiday gatherings.
Ingredients
Scale
Onions and Seasonings
- 3 pounds Vidalia or sweet onions (about 4 large), cut crosswise into 1/4-inch-thick slices
- 1 1/2 teaspoons kosher salt
- 1 teaspoon dry mustard powder
- 1 teaspoon garlic powder
- 1 teaspoon smoked paprika
- 1/4 teaspoon cayenne pepper (optional)
Cheeses and Butter
- 4 ounces mild cheddar cheese, shredded (about 1 cup), divided
- 4 ounces smoked Gouda or cheddar cheese, shredded (about 1 cup), divided
- 1 1/4 ounces grated Parmesan cheese (about 1/3 cup store-bought grated)
- 4 tablespoons (1/2 stick) unsalted butter, diced
Others
- Cooking spray
- 2 tablespoons finely chopped fresh parsley leaves, for garnish (optional)
Instructions
- Prepare the oven and baking dish: Preheat your oven to 350ºF. Lightly coat a 9×13-inch baking dish with cooking spray to prevent sticking.
- Season the onions: Separate the sliced Vidalia onions into rings and place them in a large bowl. Add kosher salt, dry mustard powder, garlic powder, smoked paprika, and optional cayenne pepper. Toss everything together thoroughly to evenly coat the onions with the seasoning.
- Layer the first half of onions and cheeses: Spread half of the onion rings evenly in the prepared baking dish. Sprinkle evenly with half of the shredded mild cheddar cheese and half of the shredded smoked Gouda cheese.
- Add the second layer: Arrange the remaining onion rings on top of the first layer. Then sprinkle with the remaining shredded mild cheddar and smoked Gouda cheeses followed by an even layer of grated Parmesan cheese.
- Add butter and cover: Scatter the diced unsalted butter over the top layer to add richness and help with browning. Cover the baking dish tightly with aluminum foil to ensure even cooking and moisture retention.
- Bake the casserole: Place the baking dish in the oven and bake for about 45 minutes until the onions are soft and the casserole is bubbling.
- Uncover and brown: Remove the foil and continue baking for an additional 30 minutes until the cheese on top is melted and has browned spots, creating a delicious crust.
- Garnish and serve: Remove from the oven, sprinkle with freshly chopped parsley if desired, and serve warm as a rich, cheesy side dish.
Notes
- Vidalia onions or other sweet onions are recommended for their natural sweetness that balances the spices and cheeses.
- Adjust cayenne pepper according to your preferred spice level or omit for a milder dish.
- Using a mix of mild cheddar and smoked Gouda cheeses adds depth of flavor with a balance of creaminess and smokiness.
- Covering the dish during initial baking helps soften the onions; uncovering finishes with a browned cheesy top.
- Fresh parsley is optional but adds a bright, fresh flavor and a pop of color.
