Caramelized Onion Tart

Name: Caramelized Onion Tart
Prep time: 20 min
Cook time: 40 min
Total time: 1 h
Yield: 8 servings
Ingredients: 1 sheet of puff pastry; 4 large onions, thinly sliced; 2 tablespoons olive oil; 1 tablespoon butter; 1 teaspoon salt; 1 teaspoon sugar; 3 large eggs; 1 cup heavy cream; 1 cup grated Gruyère cheese; Fresh thyme for garnish

Highlighted under: Classic Comfort Cooking

Delight in the savory goodness of a Caramelized Onion Tart, featuring sweet, golden onions nestled in a flaky pastry shell.

Created by

Emma

Last updated on 2025-12-03T22:14:27.651Z

This Caramelized Onion Tart is a delicious blend of sweet and savory flavors, perfect for a light lunch or a fancy appetizer. The caramelized onions bring a rich depth to the dish, complemented by a creamy filling and a flaky crust.

        Why You'll Love This Recipe
        Sweet and savory balance from the caramelized onions
Flaky, buttery pastry that melts in your mouth
Perfect for gatherings or a special dinner

      

A Flavorful Journey with Caramelized Onions

Caramelized onions are the star of this tart, bringing a rich, sweet flavor that perfectly contrasts with the sharpness of Gruyère cheese. The slow cooking process transforms the onions, releasing their natural sugars and creating a deep, complex taste. This dish showcases how a simple ingredient can elevate a meal, making it a favorite for both casual dinners and festive gatherings.

The beauty of this tart lies not only in its taste but also in its presentation. The golden, caramelized onions arranged atop the flaky pastry create an inviting visual appeal. It’s a dish that encourages sharing, whether at a family dinner or a sophisticated soirée. Serving this tart is sure to impress your guests and leave them asking for the recipe.

Perfect Pairings

To complement the savory flavors of the Caramelized Onion Tart, consider pairing it with a light mixed greens salad drizzled with a tangy vinaigrette. The freshness of the greens balances the richness of the tart, creating a harmonious dining experience. Additionally, a glass of crisp white wine, such as Sauvignon Blanc or a lightly oaked Chardonnay, would enhance the dish's flavors beautifully.

For a heartier meal, serve the tart alongside a bowl of creamy tomato basil soup. The tart's flaky texture and the soup's warmth create a delightful contrast. This combination not only satisfies hunger but also elevates the overall flavor profile, making your meal a memorable one.

Storage and Reheating Tips

Ingredients

For the Tart

1 sheet of puff pastry
4 large onions, thinly sliced
2 tablespoons olive oil
1 tablespoon butter
1 teaspoon salt
1 teaspoon sugar
3 large eggs
1 cup heavy cream
1 cup grated Gruyère cheese
Fresh thyme for garnish

These ingredients will create a deliciously rich Caramelized Onion Tart.

Steps

Prepare the Pastry

Preheat your oven to 400°F (200°C). Roll out the puff pastry on a lightly floured surface and fit it into a tart pan. Trim the edges and prick the bottom with a fork.

Bake for 10 minutes until lightly golden.

Caramelize the Onions

In a large skillet, heat olive oil and butter over medium heat. Add the sliced onions, salt, and sugar. Cook, stirring occasionally, for about 25-30 minutes until the onions are golden brown and caramelized.

Make the Filling

In a bowl, whisk together the eggs and heavy cream. Stir in the grated Gruyère cheese and season with salt and pepper.

Assemble the Tart

Spread the caramelized onions evenly over the baked pastry. Pour the egg and cheese mixture on top. Bake for an additional 25 minutes or until the filling is set and golden.

Serve

Allow the tart to cool slightly before slicing. Garnish with fresh thyme and serve warm or at room temperature.

Enjoy your delicious Caramelized Onion Tart!

Tips for Success

To ensure your onions caramelize perfectly, use a heavy-bottom skillet and cook them slowly over medium heat. This allows the natural sugars to develop without burning. Stir them occasionally and be patient; the caramelization process takes time but is well worth the effort for the depth of flavor it adds to the tart.

When working with puff pastry, keep it cold before rolling it out. This helps achieve a flaky texture after baking. If the pastry becomes too warm, pop it in the fridge for a few minutes before continuing. Additionally, don’t skip pricking the bottom of the pastry; this prevents it from puffing up too much while baking.

Variations to Try

Feel free to experiment with different types of cheese for a unique twist on this tart. Aged cheddar or even crumbled feta can add a distinctive flavor profile. You can also incorporate additional herbs like rosemary or sage for an aromatic boost that complements the sweetness of the onions.

For a vegetarian option, consider adding sautéed mushrooms or spinach to the filling. These ingredients not only enhance the tart's flavor but also increase its nutritional value, making it a wholesome dish suitable for various dietary preferences.

Questions About Recipes

→ Can I use a different type of cheese?

Yes, you can substitute Gruyère with other cheeses like cheddar or goat cheese.

→ How do I store leftovers?

Store in an airtight container in the refrigerator for up to 3 days.

→ Can I freeze the tart?

Yes, you can freeze the baked tart for up to 2 months. Thaw and reheat before serving.

→ What can I serve with the tart?

This tart pairs well with a light salad or roasted vegetables.