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Caramelized Onion Cheese Tart

Caramelized Onion Cheese Tart


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  • Author: Lina
  • Total Time: 55 minutes
  • Yield: 8 servings 1x
  • Diet: Gluten Free (if using gluten-free puff pastry)

Description

A delicious Caramelized Onion Cheese Tart featuring slowly caramelized sweet onions, rich melted Gruyere or sharp cheddar cheese, and a flaky, buttery puff pastry crust. Perfect for brunch, casual dinners, or as a savory snack with versatile serving options and easy preparation.


Ingredients

Scale

Vegetables & Herbs

  • 2 large yellow or sweet onions, thinly sliced
  • 1 teaspoon fresh thyme leaves

Fats & Oils

  • 2 tablespoons unsalted butter
  • 1 tablespoon olive oil
  • 1 egg (for egg wash)

Dairy

  • 1 1/2 cups shredded Gruyere or sharp white cheddar cheese

Others

  • 1 sheet store-bought puff pastry, thawed
  • Salt, to taste
  • Freshly ground black pepper, to taste

Instructions

  1. Prepare the Onions: Thinly slice the onions. Heat butter and olive oil in a wide pan over medium-low heat. Add the onions and cook slowly for 30-40 minutes, stirring frequently until golden brown, sweet, and fully softened.
  2. Prepare the Puff Pastry: Roll out puff pastry on a lightly floured surface to fit your tart pan or baking sheet. Prick the base lightly with a fork to prevent excessive puffing. Brush the edges with beaten egg wash for a golden crust later.
  3. Assemble the Tart: Spread the caramelized onions evenly over the pastry, leaving a small border around edges. Sprinkle shredded cheese generously over the onions. Scatter fresh thyme leaves on top for aroma and subtle earthiness.
  4. Bake Until Golden: Place tart in a preheated oven at 400°F (200°C). Bake for 20-25 minutes, until puff pastry is puffy and golden, and cheese is melted and bubbly.
  5. Cool and Serve: Remove from oven and let the tart rest for 5 minutes before slicing to allow cheese to set and flavors to meld.

Notes

  • Cook onions on low heat for best caramelization without burning.
  • Use fresh, flavorful cheese to avoid a bland tart.
  • Keep puff pastry chilled until ready to bake to ensure maximum flakiness.
  • Make sure onions are fully caramelized to develop sweetness.
  • Brushing the pastry edges with egg wash enhances a glossy, appetizing golden finish.
  • Prep Time: 15 minutes
  • Cook Time: 40 minutes
  • Category: Appetizers
  • Method: Baking
  • Cuisine: French-inspired

Nutrition

  • Serving Size: 1 slice (1/8 of tart)
  • Calories: 320
  • Sugar: 6g
  • Sodium: 350mg
  • Fat: 22g
  • Saturated Fat: 10g
  • Unsaturated Fat: 8g
  • Trans Fat: 0g
  • Carbohydrates: 20g
  • Fiber: 2g
  • Protein: 8g
  • Cholesterol: 65mg