Description
Tennessee Onions is a savory baked casserole featuring sweet yellow onions seasoned with garlic, herbs, and spices, layered generously with a blend of sharp cheddar, mozzarella, and Parmesan cheeses, then baked until bubbly and golden. This comforting side dish highlights the natural sweetness of onions enhanced by rich, melted cheeses and a hint of spice.
Ingredients
Onion Mixture
- 2½ lbs yellow onions (sweet varieties such as Vidalia or Walla Walla), sliced about ¼-inch thick
- 1 tsp garlic powder
- ½ tsp oregano
- ¼ tsp dry mustard powder
- ¼ tsp salt
- ¼ tsp black pepper
- 1 pinch cayenne pepper (optional)
Butter
- 4 Tbsp salted butter, cut into approximately ½ tablespoon pats
Cheese Blend
- 1 cup sharp cheddar cheese, shredded
- 1 cup mozzarella cheese, shredded (or substitute gouda or Monterey Jack)
- ½ cup Parmesan cheese, shredded
Instructions
- Preheat: Preheat your oven to 350°F (175°C/Gas Mark 4) and butter a 9×13-inch baking dish to prevent sticking.
- Slice Onions: Slice the yellow onions into approximately ¼-inch thick rings. Spread the onion slices evenly in the prepared baking dish.
- Season: Sprinkle the garlic powder, oregano, dry mustard powder, salt, black pepper, and optional cayenne pepper evenly over the onions to infuse flavor.
- Add Butter: Distribute the 4 tablespoons of butter, cut into small pats, evenly over the seasoned onions throughout the dish.
- Layer Cheese: Spread the shredded cheddar cheese evenly over the onions, followed by the mozzarella cheese and then the Parmesan cheese. Push the cheese to the edges for even coverage.
- Bake: Bake in the preheated oven for 40-45 minutes, or until the cheese has melted completely and is bubbly, and the onions have softened tenderly. For a golden brown top, optionally broil for 2-3 minutes at the end of baking, watching carefully to avoid burning.
- Serve: Remove from the oven and serve immediately while hot and cheesy for the best flavor and texture.
Notes
- Sweet onions such as Vidalia or Walla Walla work best for natural sweetness and mellow flavor.
- Adjust seasoning to taste, especially salt and cayenne pepper depending on preference.
- Cheese types can be substituted based on availability or taste; gouda or Monterey Jack are good alternatives for mozzarella.
- To achieve a crispier cheese topping, use the broiler for the last couple of minutes, but watch closely to prevent burning.
- This dish serves well as a side for meats or as a comforting vegetarian main with a side salad.
- Prep Time: 10 minutes
- Cook Time: 40-45 minutes
- Category: Side Dish
- Method: Baking
- Cuisine: Southern United States
