When it comes to indulgent yet easy-to-make dishes, few can rival the sheer delight of a Caramelized Onion & Gruyère Puff Pastry Slab with Thyme. This savory treat transforms simple ingredients into a rich and decadent pastry that’s perfect for impressing guests at brunch or satisfying your family on a cozy weeknight. The sweet, buttery flavor of caramelized onions melds beautifully with the nutty Gruyère cheese, while the thyme adds a fragrant touch that elevates this dish to gourmet status, all tucked into delicate puff pastry.

Why you’ll love this dish

This recipe is not just about flavor; it’s a celebration of textures and aromas. The mixture of buttery, flaky pastry and golden, caramelized onions will fill your kitchen with an irresistible scent, making it an ideal choice for gatherings or special occasions. Plus, it’s remarkably simple to prepare—perfect for both novice cooks and seasoned chefs looking for a quick yet impressive dish.

“I served this Caramelized Onion & Gruyère Puff Pastry at a family gathering, and it was the hit of the evening! Everyone raved about the flavors, and I loved how easy it was to make.”

Preparing Caramelized Onion & Gruyère Puff Pastry Slab with Thyme

This delightful dish comes together in just a few straightforward steps. You’ll start by caramelizing the onions to unlock their natural sweetness, which adds depth to the dish. While that’s happening, have your puff pastry ready to go. Spread the onions, sprinkle on the Gruyère and thyme, and you’ll have a rustic yet sophisticated slab ready for the oven in no time.

What you’ll need

Gather these items to bring this recipe to life:

• 1 sheet puff pastry, thawed (250 g)
• 3 large yellow onions, thinly sliced (450 g)
• 2 tablespoons butter (30 g)
• 1 tablespoon olive oil (15 ml)
• 1/2 teaspoon salt (3 g)
• 1 1/2 cups Gruyère cheese, grated (150 g)
• 1 teaspoon fresh thyme leaves (1 g)
• 1 large egg, beaten (1 egg / 50 g)

For a lighter version, try using a mix of low-fat cheeses, and feel free to swap thyme for other herbs like rosemary or oregano for a different flavor profile.