Alsace Onion Tart (Tarte à l’Oignon)

Name: Alsace Onion Tart (Tarte à l’Oignon)
Prep time: 1 h
Cook time: 45 min
Total time: 1 h 45 min
Cuisine: French
Ingredients: 2 cups all-purpose flour (plus more for dusting); ¾ teaspoon salt; 12 tablespoons butter (cold; cut into cubes); 5 tablespoons water (cold); 1 teaspoon cider vinegar; 4 slices thick-cut bacon (cut crosswise into strips); 2 pounds onions (halved lengthwise and very thinly sliced crosswise (10 cups)); 1 ¼ teaspoons salt; 1 teaspoon ground black pepper; 1 cup heavy cream; 4 large eggs; 2 egg yolks; ½ teaspoon freshly grated nutmeg; 2 tablespoons Fresh thyme (chopped); ½ cup grated Gruyere cheese

Instructions

Prep:1hCook:45min

A classic French onion tart from Alsace, this savory pastry layers caramelized onions, smoky bacon, and Gruyère in a rich, creamy custard baked inside a flaky butter crust. With hints of thyme and nutmeg, this Alsatian onion tart is comforting, aromatic, and perfect served warm or at room temperature for brunch, lunch, or a light dinner.

Updated at: Tue, 23 Dec 2025 05:22:33 GMT