If you love the rich, caramelized flavors of French onion soup but want something a little lighter and more elegant, this French Onion Tart Recipe is exactly what you’ve been craving. It brings together a crisp, buttery pastry base layered with savory sweet onions, nutty gruyere cheese, and fresh herbs for a beautiful, melt-in-your-mouth experience. Whether it’s for a brunch gathering or a cozy dinner, this tart feels both fancy and comforting all at once.
Ingredients You’ll Need
These ingredients are simple yet essential, each playing a crucial role in building the perfect balance of texture, flavor, and aroma in your French Onion Tart Recipe. From the flaky crust to the luscious onions and cheese, everything works harmoniously to create a dish you’ll want to make again and again.
- 2 cups all purpose flour: The foundation for your tart crust, providing structure and tenderness.
- 1/2 tsp kosher salt: Enhances flavor without overpowering the delicate balance.
- 1 Tbsp sugar: Adds a touch of sweetness that deepens the crust’s flavor.
- 12 Tbsp cold unsalted butter, diced: Key to a flaky, buttery crust that melts in your mouth.
- 1/2 cup ice water: Binds the dough while keeping it cool to maintain flakiness.
- 1 cup gruyere cheese, shredded: Offers a nutty, creamy richness that complements the onions.
- 1 1/2 tsp fresh thyme, minced: Provides a subtle earthiness to lift the tart.
- 2 tsp fresh chives, minced: Adds a mild onion-like freshness and vibrant color.
- 1 1/4 lbs sweet onions (about 3 medium): The star ingredient, caramelized to sweet perfection.
- 1 Tbsp heavy cream: Brushed over onions for a luxurious, slightly creamy finish.
- 3 Tbsp unsalted butter, diced: Dotted over onions for extra richness and flavor.
- 1 tsp kosher salt: Balances and enhances the sweetness of the onions.
How to Make French Onion Tart Recipe
Step 1: Prepare the Pastry
Start by making your tart dough to perfection. In a food processor, combine flour, salt, and sugar for a well-seasoned base. Then add the cold, diced butter and pulse until it resembles small peas—this is what gives you that wonderful flaky texture. Gradually add the ice water while pulsing until the dough just begins to come together. Quickly shape it into a ball, wrap it tightly, and refrigerate for at least one hour. This resting phase is vital—it lets the gluten relax and keeps the butter cold, resulting in a tender, crisp crust.
Step 2: Roll and Chill the Dough
Once chilled, roll the dough out between two sheets of wax paper to protect its delicate texture. Trim it precisely to a 10 x 14 inch rectangle for an even tart. After placing the rolled dough on a parchment-lined sheet pan, pop it back in the fridge while you prepare the luscious onion topping. This chilling step helps the crust hold its shape when baking, ensuring beautiful edges and a crisp bottom.
Step 3: Layer Cheese and Herbs
Sprinkle the grated gruyere evenly over the chilled crust, pushing it all the way to the edges for a cheesy, flavorful base layer. Then scatter the fresh thyme and chives on top. These herbs add an aromatic lift and a pop of color, complementing the richness of the cheese and the sweetness of the onions perfectly.
Step 4: Caramelize and Arrange Onions
Peel and slice your sweet onions very thinly into delicate half-moons, keeping their shape intact. Layer these diagonally across the tart, overlapping them just enough to create a stunning pattern. Brush the onions lightly with heavy cream, dot with small cubes of butter, and sprinkle with kosher salt. This combination will coax out the onions’ natural sweetness and give the tart that signature golden-baked finish.
Step 5: Bake to Perfection
Pop your tart into a preheated 400°F oven and bake for about 40 minutes until the pastry turns golden brown and the onions soften and caramelize beautifully. Keep an eye on the edges and cover them with foil if they start to brown too quickly. Once out of the oven, allow the tart to cool slightly so the flavors settle and the cheese firms up just enough for easy slicing.
How to Serve French Onion Tart Recipe
Garnishes
To elevate your French Onion Tart Recipe even further, sprinkle freshly chopped chives or a few whole thyme leaves over the top just before serving. A light drizzle of extra virgin olive oil or a touch of flaky sea salt can also add a lovely finishing touch that brings out all the deep, caramelized flavors.
Side Dishes
This tart shines beautifully alongside a crisp green salad with a tangy vinaigrette to contrast the richness. Alternatively, serve it with a bowl of roasted root vegetables or a simple soup for a wholesome meal. It’s versatile enough to work as a main, appetizer, or side.
Creative Ways to Present
Impress your guests by cutting the tart into elegant squares or rustic wedges, then serve on wooden boards or petite plates with fresh herbs scattered around. You can also try mini tartlets using this recipe for charming individual portions at a party. The lovely golden color and layered textures make it a visual standout wherever it lands.
Make Ahead and Storage
Storing Leftovers
Your French Onion Tart Recipe leftovers keep beautifully in the fridge for up to three days when wrapped tightly with plastic wrap or stored in an airtight container. The flavors often deepen overnight, making the next-day tart even tastier.
Freezing
To freeze, cool the tart completely, then wrap it firmly with plastic wrap followed by foil. It can be frozen for up to one month. Thaw overnight in the refrigerator before reheating to keep the crust from becoming soggy.
Reheating
Reheat leftovers in a preheated oven at 350°F for 10 to 15 minutes until warmed through and crisp on the edges. Avoid microwaving if possible, as it will soften the crust and dull the flavors.
FAQs
Can I use other cheeses besides gruyere in this tart?
Absolutely! While gruyere offers a lovely nutty flavor, you can experiment with Swiss, fontina, or even a sharp cheddar. Just choose cheeses that melt well for that creamy texture.
How can I tell when the onions are caramelized enough?
The onions should be softened and golden brown with a sweet aroma, not burnt. They’ll have a rich color but still retain a little texture to keep the tart from becoming mushy.
Is it okay to use frozen pastry dough instead of making my own?
You can use frozen puff pastry or pie dough for convenience. Just be mindful the flavor and texture won’t be quite as rich as homemade, but it still makes a tasty tart.
Can I make this tart gluten-free?
Yes, substitute the all-purpose flour with your favorite gluten-free baking blend. Just be sure to adjust water content slightly as gluten-free doughs behave differently.
What’s the best way to serve this tart for a party?
Cut it into bite-sized squares or mini tartlets for easy finger food. Serve with toothpicks or small forks to make it a hit at any gathering.
Final Thoughts
There’s something so utterly satisfying about making and sharing this French Onion Tart Recipe. It’s a dish that feels special yet approachable, with comforting flavors that delight every time. I can’t wait for you to try it and enjoy those golden, cheesy, sweet onion layers as much as I do. Trust me, once you do, this tart will become a beloved classic in your cooking rotation.
PrintFrench Onion Tart Recipe
This classic French Onion Tart features a flaky homemade pastry crust filled with sweet caramelized onions, melted Gruyere cheese, and fragrant fresh herbs. Perfect as an elegant appetizer or a light meal, the tart combines savory flavors with a rich buttery crust baked to golden perfection.
- Prep Time: 20 minutes
- Cook Time: 50 minutes
- Total Time: 1 hour 10 minutes
- Yield: 8 servings
- Category: Appetizer
- Method: Baking
- Cuisine: French
Ingredients
Pastry
- 2 cups all purpose flour
- 1/2 tsp kosher salt
- 1 Tbsp sugar
- 12 Tbsp cold unsalted butter, diced (1 1/2 sticks)
- 1/2 cup ice water
Filling
- 1 cup Gruyere cheese, shredded (4 oz)
- 1 1/2 tsp fresh thyme, minced
- 2 tsp fresh chives, minced
- 1 1/4 lbs sweet onions (about 3 medium onions)
- 1 Tbsp heavy cream
- 3 Tbsp unsalted butter, diced
- 1 tsp kosher salt
Instructions
- Make the Pastry: Place the flour, kosher salt, and sugar into the bowl of a food processor fitted with the steel blade. Pulse briefly a few times to combine the dry ingredients.
- Incorporate Butter: Add the diced cold unsalted butter to the food processor and pulse 10 to 12 times until the butter pieces resemble small peas in size, ensuring the dough will be flaky.
- Add Ice Water: While the motor is running, slowly pour the ice water down the feed tube and pulse just until the dough begins to come together. Avoid overmixing to keep the pastry tender.
- Form and Chill Dough: Dump the dough onto a lightly floured board and quickly knead it into a ball. Wrap the dough tightly with plastic wrap and refrigerate it for at least 1 hour to firm up before rolling.
- Preheat Oven and Prepare Baking Sheet: Preheat your oven to 400°F (200°C) and line a sheet pan with parchment paper to prevent sticking and ensure even baking.
- Roll Out Dough: Roll the chilled dough between two sheets of lightly floured wax paper into a rectangle slightly larger than 10 by 14 inches. Trim the edges neatly with a ruler and a small knife, then transfer the dough onto the prepared sheet pan. Refrigerate again while preparing the filling.
- Add Cheese and Herbs: Evenly sprinkle the shredded Gruyere cheese over the rolled-out pastry right to the edges. Next, sprinkle the minced fresh thyme and chives over the cheese for fresh herbal flavor.
- Prepare Onions: Peel, halve, and very thinly slice the sweet onions into half moon shapes, keeping the slices intact to layer neatly on the tart.
- Arrange Onions: Lay the sliced onion half moons diagonally over the cheese-covered pastry, slightly overlapping each slice in tidy lines.
- Brush and Season: Lightly brush the arranged onions with heavy cream to add richness. Dot the top with diced unsalted butter and sprinkle with kosher salt to enhance the savory flavors.
- Bake the Tart: Place the tart in the preheated oven and bake for 40 minutes or until the crust is golden brown and the cheese is bubbling. If the edges brown too quickly, cover them with foil to prevent burning.
- Cool and Serve: Remove the tart from the oven and allow it to cool slightly. Cut into squares and serve warm or at room temperature for the best flavor and texture.
Notes
- Use cold butter for the pastry to ensure a flaky crust.
- Keep the onions sliced evenly for even cooking and an attractive presentation.
- If you prefer a sweeter onion flavor, you can caramelize the onions beforehand, but the recipe works well with raw sliced sweet onions.
- Cover the tart edges with foil partway through baking if they brown too quickly to avoid burning.
- Gruyere cheese can be substituted with Comté or Emmental for a similar flavor profile.
- Serve the tart as an appetizer, brunch dish, or light dinner paired with a simple salad.
