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Caramelized Onion Butternut Squash Tart

Caramelized Onion Butternut Squash Tart

This Caramelized Onion Butternut Squash Tart is a beautiful, savory, and slightly sweet dish perfect for fall gatherings, holiday tables, or cozy weeknight dinners. Made with roasted butternut squash, buttery caramelized onions, fresh herbs, and a flaky crust, it brings together everything you love about butternut squash recipes roasted and elegant tarts. Whether you're a fan of baked butternut squash, stuffed butternut squash, or even roasted acorn squash, this tart delivers rich flavor in every bite.
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Prep Time 20 minutes
Cook Time 50 minutes
Total Time 1 hour 10 minutes
Servings: 4
Ingredients Method Notes

Ingredients
  

  • For the Tart
  • 1 sheet puff pastry thawed
  • 2 cups butternut squash peeled & cubed
  • 2 tbsp olive oil
  • Salt & black pepper to taste
  • 1 tsp thyme dried or fresh
  • 1 cup Gruyère cheese shredded
  • ½ cup ricotta cheese or cream cheese optional for a creamier tart
  • For the Caramelized Onions
  • 2 large yellow onions thinly sliced
  • 2 tbsp butter
  • 1 tbsp olive oil
  • 1 tsp sugar helps onions caramelize faster
  • ½ tsp salt
  • 1 tbsp balsamic vinegar optional, for depth

Method
 

  1. Step 1 — Roast the Butternut Squash
  2. Preheat the oven to 400°F (200°C).
  3. Place butternut squash cubes on a baking sheet.
  4. Drizzle with 2 tbsp olive oil, add salt, pepper, and thyme.
  5. Toss to coat and roast for 20–25 minutes or until tender and slightly caramelized.
  6. Step 2 — Caramelize the Onions
  7. In a large skillet, heat butter and olive oil over medium heat.
  8. Add sliced onions and sauté for 3–4 minutes.
  9. Sprinkle with sugar and salt.
  10. Reduce heat to medium-low and cook 20–25 minutes, stirring occasionally, until onions are deep golden.
  11. Add balsamic vinegar if desired and cook 2 more minutes.
  12. Step 3 — Prepare the Puff Pastry
  13. Reduce oven temperature to 375°F (190°C).
  14. Roll out the puff pastry sheet on parchment paper.
  15. Transfer the pastry to a baking tray.
  16. Use a knife to lightly score a 1-inch border around the edges (do not cut through).
  17. Poke the inside area with a fork to prevent puffing.
  18. Step 4 — Assemble the Tart
  19. Spread ricotta (if using) over the pastry inside the scored border.
  20. Add grated Gruyère evenly over the surface.
  21. Top with caramelized onions.
  22. Add roasted butternut squash on top.
  23. Step 5 — Bake
  24. Bake for 20–22 minutes, or until the edges are golden and the cheese is bubbly.
  25. Remove from the oven and cool for 5 minutes before slicing.
  26. Step 6 — Serve
  27. Slice into squares or triangles.
  28. Serve warm or at room temperature.
  29. Perfect for brunch, parties, fall dinners, or holiday spreads.

Notes

You can substitute acorn squash or delicata squash.
For extra flavor, add fresh sage, rosemary, or thyme on top after baking.
Add crumbled goat cheese or feta for a tangy twist.
To make it sweeter, drizzle with honey or maple syrup before serving.
Store leftovers in an airtight container for up to 3 days; reheat in the oven to keep pastry crisp.
For a richer onion flavor, caramelize onions longer (up to 40 minutes).
Works great as an appetizer, side dish, or vegetarian main course.