Save to Pinterest Acorn squash halves roasted until tender, stuffed with deeply caramelized onions and melty Gruyere cheese, and finished with fresh herbs—a comforting, gourmet vegetarian main perfect for any occasion.
This recipe combines roasted acorn squash with sweet caramelized onions and rich Gruyere cheese for a dish my family enjoys all year round.
Ingredients
- Squash: 2 medium acorn squash, halved lengthwise and seeded, 2 tablespoons olive oil, 1/2 teaspoon kosher salt, 1/4 teaspoon ground black pepper
- Caramelized Onions: 2 large yellow onions, thinly sliced, 2 tablespoons unsalted butter, 1 tablespoon olive oil, 1/2 teaspoon kosher salt, 1/2 teaspoon granulated sugar, 2 teaspoons balsamic vinegar
- Filling and Garnish: 1 1/2 cups Gruyere cheese, grated, 2 tablespoons fresh thyme leaves plus more for garnish, 1/4 cup chopped fresh parsley (optional)
Instructions
- Preheat oven:
- Preheat oven to 400℉ (200℃). Line a baking sheet with parchment paper.
- Prepare squash:
- Brush the cut sides of the acorn squash with olive oil. Season with kosher salt and black pepper. Place squash halves cut side down on the prepared baking sheet and roast for 35–40 minutes, or until the flesh is fork-tender.
- Caramelize onions:
- Meanwhile, heat unsalted butter and olive oil in a large skillet over medium-low heat. Add the sliced onions and kosher salt. Cook, stirring occasionally, for 30–35 minutes until the onions are deeply golden and soft. Sprinkle with sugar about halfway through to encourage caramelization.
- Add vinegar and thyme:
- Stir in the balsamic vinegar and fresh thyme. Cook for 2 minutes, then remove from heat.
- Prepare squash for filling:
- Remove squash from the oven and carefully turn cut side up. Reduce oven temperature to 375℉ (190℃).
- Fill squash:
- Evenly distribute the caramelized onions among the squash cavities. Top each half with grated Gruyere cheese.
- Bake filled squash:
- Return the filled squash to the oven and bake for 15–20 minutes, or until the cheese is melted and golden brown at the edges.
- Garnish and serve:
- Remove from the oven. Garnish with fresh parsley and additional thyme leaves before serving.
Save to Pinterest Sharing this meal with my family always brings a warm, joyous moment around the dinner table.
Notes
Roast squash cut side down to concentrate sweetness and enhance caramelization. Caramelize onions slowly over low heat to avoid burning and bitterness. Grate cheese yourself for the best melting texture. Easily doubled for meal prep or gatherings. Pairs beautifully with a green salad or crispy sourdough toast. Use certified gluten-free cheese if needed.
Required Tools
Chefs knife, cutting board, baking sheet, parchment paper, large skillet, wooden spoon, grater
Allergen Information
Contains dairy (butter, Gruyere cheese). Naturally gluten-free always check cheese labels to confirm. Vegetarian-friendly. No nuts or soy in the base recipe but verify all ingredient labels for cross-contamination if needed.
Save to Pinterest This dish combines sweet, savory, and creamy elements for a truly delightful meal.
Common Recipe Questions
- → How do you caramelize onions perfectly?
Cook sliced onions slowly over low heat with butter and oil, stirring occasionally for 30-35 minutes. Sprinkle sugar mid-way to enhance caramelization without burning.
- → Why roast squash cut side down?
Roasting acorn squash cut side down concentrates sweetness and encourages even cooking, resulting in tender, flavorful flesh.
- → Can I use other cheeses instead of Gruyere?
Yes, cheeses like Swiss or fontina can be substitutes, offering similar melt quality and mild nutty flavor.
- → What herbs complement this dish best?
Fresh thyme and parsley enhance the savory and fresh notes, balancing the richness of caramelized onions and cheese.
- → Is this dish suitable for gluten-free diets?
Yes, the dish is naturally gluten-free; just ensure your cheese and other ingredients are certified gluten-free.