Tarte à l’Oignon: Savory French Onion Tart with Cream and Cheese
This delightful tart from the Alsace region of France is like a cousin of quiche—lightly caramelized onions nestled in a buttery crust, enriched with cream, eggs, and a touch of cheese. It’s elegant, comforting, and perfect for brunch, lunch, or even a light dinner with a green salad and chilled white wine.

🥧 Ingredients (Serves 4–6)
For the Crust:
- 1¼ cups all-purpose flour
- ½ tsp salt
- 8 tbsp (1 stick) unsalted butter, chilled and cut into cubes
- 3–4 tbsp ice water
For the Filling:
- 2 tbsp unsalted butter
- 3 large yellow onions, thinly sliced
- ½ tsp salt
- ½ tsp sugar
- ¾ cup heavy cream
- 2 large eggs
- ½ cup grated Gruyère or Swiss cheese
- Ground black pepper, to taste
- A pinch of freshly grated nutmeg (optional)
🔪 Instructions
Make the Tart Crust: In a bowl or food processor, mix flour and salt. Cut in the cold butter until it resembles coarse crumbs. Add ice water, a tablespoon at a time, until dough just comes together. Flatten into a disk, wrap in plastic, and refrigerate for at least 30 minutes.
Cook the Onions: Melt butter in a large skillet over medium-low heat. Add onions, salt, and sugar. Cook slowly, stirring often, for 20–25 minutes until soft and golden (but not deeply caramelized). Let cool slightly.
Prepare the Filling: In a bowl, whisk together cream, eggs, cheese, pepper, and nutmeg. Stir in the cooked onions.

Assemble the Tart: Preheat oven to 375°F (190°C). Roll out the chilled dough on a floured surface and press it into a 9-inch tart pan. Trim edges and prick the base with a fork. Pour the onion mixture into the crust.
Bake: Place tart on a baking sheet and bake for 35–40 minutes, or until the center is set and the top is golden. Cool slightly before slicing.
📦 Amazon Must-Haves to Help You Create the Best Tarte à l’Oignon
- 🥧 Tart Pan with Removable Bottom — Makes serving and cleanup easy while giving your tart a crisp edge.
- 🔪 Mandoline Slicer for Thin Onions — Slice onions evenly and effortlessly for a uniform texture.
- 🧈 European-Style Butter — Rich and creamy, perfect for authentic French flavor.
- 🧅 Sweet Yellow Onions — Essential for the mild, caramelized base of the tarte.
- 🧀 Gruyère Cheese Block or Shreds — Melts beautifully and adds nutty, savory depth.
Pro Tip: Let the tart cool for about 10 minutes before slicing—it sets up beautifully and makes serving easier.