Caramelized Onion Gruyère Square Acorn Squash Recipe

Introduction

This Caramelized Onion Gruyère Squash is a cozy and flavorful dish perfect for fall. Roasted acorn squash is topped with sweet caramelized onions and melted Gruyère cheese, making it an irresistible side or vegetarian main. Simple to prepare, it brings warmth and comfort to any meal.

Ingredients

• 2 medium acorn squash, halved lengthwise and seeded
• 2 tbsp olive oil (for brushing squash)
• ½ tsp kosher salt
• ¼ tsp ground black pepper
• 2 large yellow onions, thinly sliced
• 2 tbsp unsalted butter
• 1 tbsp olive oil (for onions)
• ½ tsp kosher salt (for onions)
• ½ tsp granulated sugar
• 2 tsp balsamic vinegar
• 1 ½ cups Gruyère cheese, grated
• 2 tbsp fresh thyme leaves, plus more for garnish
• ¼ cup fresh parsley, chopped (optional)

Instructions

1. Step 1: Preheat your oven to 400°F (200°C). Cut the acorn squash in half lengthwise and remove the seeds. Brush the cut sides with olive oil, sprinkle with salt and pepper, then place them cut side down on a parchment-lined baking sheet.
2. Step 2: Roast the squash for 35–40 minutes, or until fork-tender.
3. Step 3: While the squash roasts, heat butter and olive oil in a skillet over medium-low heat. Add the sliced onions and salt, cooking slowly for 30–35 minutes until they turn golden and caramelized.
4. Step 4: Halfway through cooking the onions, sprinkle in the granulated sugar to enhance caramelization. Stir occasionally.
5. Step 5: Stir in the balsamic vinegar and fresh thyme, cooking for 2 more minutes to combine flavors.
6. Step 6: Once the squash is roasted, flip the halves cut side up. Fill each with the caramelized onions, then top generously with grated Gruyère cheese.
7. Step 7: Return the squash to the oven and bake for 10–15 minutes, or until the cheese is melted and bubbly.
8. Step 8: Garnish with fresh parsley and thyme before serving.

Tips & Variations

• Swap Gruyère for sharp cheddar or Swiss cheese for a different flavor profile.
• Add a pinch of chili flakes to the onions for a subtle spicy kick.
• This dish works wonderfully as a Thanksgiving side or a cozy fall dinner centerpiece.

Storage

Store leftovers in an airtight container in the refrigerator for up to 3 days. Reheat in the oven at 350°F (175°C) until warmed through and the cheese is bubbly again. Avoid microwaving to maintain texture.

How to Serve

Serve this delicious recipe with your favorite sides.

FAQs

Can I use a different type of squash?

Yes, but choose a squash that roasts well and holds its shape, like delicata or kabocha. Cooking times may vary slightly.

How do I know when the onions are properly caramelized?

They should turn a deep golden brown, become very soft, and develop a sweet, rich flavor without burning. Stir frequently and cook slowly over medium-low heat.

Caramelized Onion Gruyère Square Acorn Squash Recipe

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★★★★★

4.9 from 106 reviews

This Caramelized Onion Gruyère Squash is a comforting and elegant vegetarian dish that combines sweet roasted acorn squash with rich, buttery caramelized onions and melty Gruyère cheese, all enhanced by fresh herbs and a touch of balsamic vinegar. Perfect as a cozy fall dinner or a festive Thanksgiving side, it delivers layers of flavor and creamy texture in every bite.

• Author: Elena
• Prep Time: 15 minutes
• Cook Time: 50 minutes
• Total Time: 1 hour 5 minutes
• Yield: 4 servings 1x
• Category: Dinner
• Method: Baking
• Cuisine: American
• Diet: Vegetarian

Ingredients

Scale 1x2x3x

Squash

• 2 medium acorn squash, halved lengthwise and seeded
• 2 tbsp olive oil for brushing squash
• ½ tsp kosher salt
• ¼ tsp ground black pepper

Caramelized Onions

• 2 large yellow onions, thinly sliced
• 2 tbsp unsalted butter
• 1 tbsp olive oil for onions
• ½ tsp kosher salt for onions
• ½ tsp granulated sugar
• 2 tsp balsamic vinegar

Other

• 1 ½ cups Gruyère cheese, grated
• 2 tbsp fresh thyme leaves, plus more for garnish
• ¼ cup fresh parsley, chopped (optional)

Instructions

1. Preheat Oven: Preheat your oven to 400°F (200°C) to prepare for roasting the squash.
2. Prepare Squash: Cut acorn squash in half lengthwise and remove the seeds. Brush the cut sides with olive oil, then sprinkle with kosher salt and ground black pepper. Place the halves cut side down on a parchment-lined baking sheet.
3. Roast Squash: Roast the squash in the preheated oven for 35 to 40 minutes, until the flesh is tender when pierced with a fork.
4. Caramelize Onions: While the squash roasts, heat butter and olive oil in a skillet over medium-low heat. Add thinly sliced onions and salt, cooking slowly for 30 to 35 minutes until they become golden and caramelized. Halfway through cooking, sprinkle the onions with granulated sugar to enhance caramelization.
5. Add Flavor to Onions: Stir in the balsamic vinegar and fresh thyme leaves, then cook the onions for an additional 2 minutes to meld the flavors.
6. Assemble Squash: Remove the roasted squash from the oven and flip the halves so the cut side is facing up. Spoon the caramelized onion mixture evenly into each squash half, then top generously with grated Gruyère cheese.
7. Final Bake: Return the assembled squash to the oven and bake for 10 to 15 minutes, or until the cheese has melted and is bubbly.
8. Garnish and Serve: Remove from oven and garnish with fresh parsley and additional thyme leaves before serving warm.

Notes

• For a different flavor, swap Gruyère for sharp cheddar or Swiss cheese.
• Add a pinch of chili flakes to the caramelized onions for a subtle kick.
• This dish works beautifully as a Thanksgiving side or a comforting fall dinner.
• Use parchment paper on the baking sheet to prevent sticking and ease cleanup.

Keywords: Fall Recipe, Squash, Vegetarian, Roasted Squash, Caramelized Onions, Gruyère Cheese