This dish is a superstar at potlucks and family dinners. Thinly sliced sweet onions are baked in a rich, buttery, cheesy sauce until meltingly tender and golden brown. It’s the ultimate comfort side dish that pairs perfectly with grilled meats, BBQ, or just a simple piece of cornbread.
Prep Time: 10 minutes | Cook Time: 40-45 minutes | Total Time: 55 minutes | Serves: 6-8
Ingredients
- 3-4 large Vidalia sweet onions (or other sweet onions like Walla Walla)
- 4 tbsp unsalted butter, thinly sliced or cubed
- 1 tsp salt
- 1 tsp garlic powder
- 1 tsp black pepper (optional but recommended)
- 1 cup shredded sharp cheddar cheese
- 1 cup shredded Monterey Jack cheese (or mozzarella for stretchiness)
- ½ cup grated Parmesan cheese
- ½ cup mayonnaise (optional, for extra creaminess)
- ½ cup sour cream (optional, for tang)
- Fresh parsley or chives, for garnish (optional)
Instructions
-
Preheat Oven & Prepare Onions:
Preheat your oven to 350°F (175°C).
Peel the onions and slice them into ¼-inch thick rounds. -
Layer the Dish:
Lightly grease a 9×13-inch baking dish.
Arrange the onion slices in a single layer (or slightly overlapping) in the dish.
Sprinkle evenly with salt, garlic powder, and black pepper.
Dot the top with thin slices or small cubes of butter. -
Add Creamy Layer (Optional but Recommended):
In a small bowl, mix the mayonnaise and sour cream (if using). Spread this mixture evenly over the onions. -
Add Cheese:
Sprinkle the shredded cheddar, Monterey Jack, and Parmesan cheeses evenly over the top. -
Bake:
Cover the dish with foil and bake for 30 minutes.
Remove the foil and bake for another 10-15 minutes, or until the cheese is bubbly and golden brown and the onions are tender. -
Garnish & Serve:
Let the dish rest for 5 minutes before serving.
Garnish with fresh parsley or chives if desired.
Serve warm as a side dish.
