Go Back
–+ servings
Caramelized Onion Tart Finished baked caramelized onion tart, golden crust, onions glossy and browned, one slice cut, styled on parchment paper with a vintage knife, minimal props.

Caramelized Onion Tart

A simple, Caramelized Onion Tart loaded with sweet, caramelized onions that melt in your mouth.
No ratings yet
Print Pin
Course: Appetizer, Main
Cuisine: French-inspired, Vegan
Keyword: caramelized onions, onion tart, puff pastry, vegan appetizer
Prep Time: 10 minutes
Cook Time: 40 minutes
Total Time: 50 minutes
Servings: 4
Calories: 337kcal
Cost: $8

Ingredients

  • 200 g puff pastry 1 sheet, thawed according to package
  • 4 red onions medium, thickly sliced
  • 1 tablespoon balsamic vinegar adds tangy sweetness
  • 1 tablespoon maple syrup natural sweetener
  • 1 teaspoon salt or to taste
  • Fresh thyme optional, for garnish
  • Olive oil for drizzling during caramelization
  • Boiling water to gently soften onions

Instructions

  • Thaw the puff pastry sheet according to package instructions.
  • Peel the onions and slice into thick rounds, roughly ½ inch each.
  • Place the onion slices in a large skillet and pour just enough boiling water to cover. Simmer over medium heat for 20 minutes, stirring occasionally, until most water evaporates.
    Caramelized onions spread evenly over the tart pastry with a layer of creamy cheese underneath.
  • Remove excess water from the skillet, then stir in balsamic vinegar, maple syrup, a drizzle of olive oil, and salt. Cook until onions are lightly browned and caramelized.
  • Preheat the oven to 400°F (200°C) and lightly oil a rectangular tart pan (approx. 8.5 x 10 inches).
  • Spread the caramelized onions evenly in the pan. Carefully lay the puff pastry over the top and gently tuck the edges around the onions.
    Puff pastry pressed into a tart pan, edges crimped, ready to fill.
  • Bake in the preheated oven for 30 minutes, until the pastry is golden brown and crisp.
    Raw puff pastry sheet on parchment paper, with three whole red onions and small bowls of olive oil and balsamic vinegar nearby.
  • Allow the tart to cool slightly, then carefully invert onto a serving board or platter. Garnish with fresh thyme if desired

Notes

Golden, sweet, and savory—this tart is perfect for cozy gatherings or a quick weeknight treat. The caramelized onions create a comforting depth of flavor that pairs beautifully with crisp puff pastry.

Nutrition

Serving: 1Serving | Calories: 337kcal (17%) | Carbohydrates: 37g (12%) | Protein: 5g (10%) | Fat: 19g (29%) | Saturated Fat: 5g (31%) | Polyunsaturated Fat: 2.5g | Monounsaturated Fat: 11g | Sodium: 710mg (31%) | Potassium: 207mg (6%) | Fiber: 2.5g (10%) | Sugar: 8.5g (9%) | Vitamin A: 3IU | Vitamin C: 8mg (10%) | Calcium: 37mg (4%) | Iron: 1.5mg (8%)
Tried this recipe?Pin it on @Pinterest