Tested till perfect Caramelized Spring Onion and Gruyère Tart
Caramelized Spring Onion and Gruyère Tart
Photography by Jeff Coulson

Caramelized Spring Onion and Gruyère Tart

To create this decadent tart, sweet spring bulb onions get cozy with mustard, balsamic vinegar and honey. A generous shower of Gruyère cheese over the pastry ensures a crisp, golden-bottomed crust. Serve with a simple tossed salad or grilled asparagus.

By Irene Fong and The Canadian Living Test Kitchen

Source: Canadian Living Magazine: May 2014

Recipe4 out of 5 based on 11 ratings.
  • rating starrating starrating starrating starrating star
  • Prep time 25 minutes
  • Total time 1 hour 30 minutes
  • Portion size 6 to 8 servings


  • Half pkg Half pkg(450 g) frozen butter puff pastry, thawed
  • 1 tsp 1tspolive oil
  • 450 g 450gspring bulb oniononions, trimmed and cut in 3/4-inch (2 cm) wedges
  • 2 tbsp 2tbspbalsamic vinegar
  • 2 tsp 2tspliquid honey
  • 1/4 tsp 1/4tspeach salt and pepper
  • 1 tsp 1tspchopped fresh thyme
  • 1 1eggeggs, beaten
  • 2 tbsp 2tbspwhipping cream 35%
  • 1 tbsp 1tbspDijon mustard
  • 1-1/4 cups 1-1/4cupsshredded Gruyère cheese
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Unroll puff pastry; press into fluted 9-inch (23 cm) tart pan with removable bottom. Line with foil; fill with pie weights or dried beans. Bake on bottom rack in 400 F (200C) oven for 20 minutes. Remove weights and foil; let cool in pan on rack.

Meanwhile, in skillet, heat oil over medium-high heat; cook onions, stirring, until golden, about 3 minutes. Add 1/4 cup water; reduce heat to medium. Cover and cook, stirring occasionally, until no liquid remains and onions are soft, about 5 to 8 minutes.

Stir in vinegar, honey and half each of the salt and pepper; cook, stirring, until onions are dark golden, about 8 minutes. Remove from heat; stir in 3/4 tsp of the thyme. Set aside.

Stir together egg, cream, mustard, and remaining salt and pepper. Sprinkle bottom of pastry with half of the Gruyère cheese; top with onion mixture. Pour egg mixture over top; sprinkle with remaining cheese and thyme.

Bake in 400 F (200 C) oven until crust is golden and knife inserted in centre comes out clean, about 25 minutes. Let stand for 10 minutes before cutting into wedges.

Nutritional Information per each of 8 servings: about

cal 243 pro 9g total fat 16g sat. fat 8g
carb 17g dietary fibre 2g sugar 4g chol 57mg
sodium 261mg potassium 182mg


calcium 20 iron 11 vit A 15 vit C 10
folate 14
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