Caramelized Onion Gruyère Tartlets
Flaky pastry shells filled with deeply caramelized onions and nutty melted Gruyère
Ingredients
- 30mini phyllo cups(frozen, thawed)
- 3 largeyellow onions(thinly sliced)
- 3 tbspbutter
- 1 tbspolive oil
- 1 tspfresh thyme leaves
- 1 tbspbalsamic vinegar
- 0.5 tspkosher salt
- 6 ozGruyère cheese(shredded)
- 2 tbspfresh chives(minced, for garnish)
📝 Make Ahead
Caramelized onions can be made up to 1 week ahead; refrigerate. Assembled tartlets can be refrigerated 4 hours before baking.
Instructions
- Heat butter and oil in large skillet over medium heat
- Add onions and salt, stir to coat
- Cook 35-45 minutes, stirring occasionally, until deeply golden and jammy
- Add thyme and balsamic vinegar in last 5 minutes
- Let onion mixture cool slightly
- Preheat oven to 350°F and arrange phyllo cups on baking sheet
- Place small pinch of Gruyère in each cup
- Top with heaping teaspoon of caramelized onions
- Add another small pinch of Gruyère on top
- Bake 8-10 minutes until cheese is melted and bubbly
- Garnish with fresh chives and serve warm
💡 Pro Tips
True caramelization cannot be rushed - low and slow is essential. A splash of water when onions start to stick helps deglaze and prevents burning. The balsamic adds color and complexity but can be omitted for a more traditional French flavor. Comté cheese is an excellent substitute for Gruyère.
📜 History
French onion soup inspired this elegant finger-food adaptation. Caramelized onions have been a cornerstone of French cooking for centuries, with the Maillard reaction transforming sharp alliums into sweet, complex, deeply flavored morsels that exemplify slow-food techniques.