Be Healthy!Start eating, feeling & living better today. Subscribe

French Onion Tart With Cheesy Thyme Pastry

6 Mins read
rustic wood table displays homemade savory pies generated by ai

You’re about to embark on a delicious journey, crafting a French Onion Tart with Cheesy Thyme Pastry.

This isn’t your everyday tart; it’s a culinary masterpiece, packed with rich, savory flavors and a unique, cheesy crust.

You’ll learn the secrets behind its ingredients and master the steps to create it.

So, roll up your sleeves and preheat the oven.

Let’s dive into the world of French cuisine and whip up this scrumptious tart together!

The History and Inspiration Behind the French Onion Tart

You’ll find the origins of the French Onion Tart in the rustic kitchens of France, where it was inspired by the classic French Onion Soup. This hearty tart evolved as a way for bakers to utilize their surplus of onions and bring out their sweet, caramelized flavors.

It’s a staple dish in many French homes, particularly in the colder months. The addition of cheesy thyme pastry is a more recent twist, adding a savory depth to the tart’s flavor profile.

Upside Down Onion and Gruyere Tarts 15

You can imagine French bakers, centuries ago, pulling this delicious dish from their ovens. It’s a piece of culinary history, a testament to French ingenuity and resourcefulness.

Ingredients Breakdown: What Makes This Tart Special

Let’s take a closer look at what ingredients make this French onion tart with cheesy thyme pastry truly unique.

You can’t ignore the onions, caramelized to perfection, providing a rich, deep flavor that’s the heart of this tart.

Then there’s the cheesy thyme pastry, a savory blend of cheese and aromatic thyme, giving the tart its characterful crust.

But it’s the combination of ingredients that really sets it apart. The sweetness of the onions, the pungent cheese, the fragrant thyme, and a splash of white wine for acidity. With every bite, you’re getting a harmonious blend of flavors that’s distinctively French.

Lastly, there’s the Gruyere cheese topping, bubbling and golden brown, adding a final layer of indulgence.

This tart is a testament to the magic that happens when simple ingredients are prepared with love and skill.

Step-by-Step Guide to Preparing Cheesy Thyme Pastry

Now, we’re moving on to the process of crafting the flavorful crust for our dish.

First, you’ll need to sift your flour and salt into a large bowl.

Upside Down Onion and Gruyere Tarts 1

Cut your butter into small pieces and add it to the bowl.

Use your fingers to rub the butter into the flour until it resembles fine breadcrumbs.

Stir in the finely grated cheese and thyme.

Now, add just enough cold water to form a dough. You’re not aiming for a wet dough, so be careful not to overdo it.

Wrap your dough in cling film and chill it in the fridge for about 30 minutes.

After chilling, roll it out on a lightly floured surface to fit your tart tin.

You’ve just made your cheesy thyme pastry!

Assembling and Baking Your French Onion Tart

With your crust prepared, it’s time to layer in your caramelized veggies before baking this savory treat. Distribute your beautifully browned onions evenly over the cheesy thyme pastry. You’ve worked hard on that crust, so don’t be shy!

Next, pour in the egg and cream mixture. This is what gives your tart its rich, custardy texture. Remember to season with a little salt and pepper too. It’s all about balancing flavors.

Now, sprinkle the top with a generous handful of Gruyere cheese. This will melt into a delicious, golden crust that’s impossible to resist. Finally, it’s into the oven it goes. Bake until it’s puffed up and golden brown.

Wait just a few minutes before slicing into it. You’re about to taste a real masterpiece!

Serving Suggestions and Pairings for Your Tart

You’re going to want to consider some wine pairings to really elevate your baked masterpiece. A crisp, dry white wine like a Chardonnay or a Sauvignon Blanc pairs beautifully with the caramelized onions and cheesy thyme pastry. The tart’s rich flavors are balanced out by the wine’s acidity, making for a delightful gastronomical experience.

Upside Down Onion and Gruyere Tarts 10

Beyond wine, think about the sides. A fresh, leafy green salad with a tangy vinaigrette can help cut through the tart’s richness. Or, if you’re more adventurous, try a lightly dressed arugula salad with slivers of prosciutto and shaved Parmesan. It’s all about balancing flavors here.

Remember, your French onion tart is the star of the show, so choose accompaniments that complement, not overshadow it.

Enjoy your culinary journey!


How Can I Store Any Leftover French Onion Tart?

You’re wondering about storing leftovers. Just let them cool, then put them in an airtight container. They’ll keep in the fridge for about 3 days. To reheat, warm in the oven. Don’t use a microwave, it’ll ruin the crust.

Can I Use a Different Type of Cheese in the Cheesy Thyme Pastry?

Absolutely, you can switch up the cheese in the pastry. It’s your dish, experiment with different types. Just remember, the cheese’s flavor and melting properties can alter the tart’s overall taste and texture.

Can This Recipe Be Adapted for a Gluten-Free Diet?

Absolutely, you can adapt this recipe for a gluten-free diet. Just use a gluten-free flour blend in place of the regular flour in the pastry. Ensure you’re also using gluten-free cheese. Enjoy your cooking!

Homemade Hot Honey 2

rustic wood table displays homemade savory pies generated by ai

French Onion Tart With Cheesy Thyme Pastry

You're about to embark on a delicious journey, crafting a French Onion Tart with Cheesy Thyme Pastry.
Prep Time 35 minutes
Cook Time 1 hour 40 minutes
Servings 10


  • 200 g plain flour plus extra for dusting
  • 100 g cold butter cubed, plus 25g
  • 150 g gruyère comté or vegetarian Italian-style hard cheese, grated
  • small handful of thyme leaves picked
  • 1 tbsp olive oil
  • 3 large onions finely sliced
  • 2 tbsp white wine or sherry vinegar
  • 1 tbsp sugar
  • 2 brown anchovies finely chopped, or use 1 tsp olive tapenade or umami paste
  • 2 large eggs
  • 300 ml double cream
  • For the rocket salad
  • 1 tbsp extra virgin olive oil
  • 2 tsp balsamic vinegar
  • 2 sundried tomatoes finely sliced
  • 6-8 pitted black olives thinly sliced
  • 1 tsp capers
  • a few handfuls of rocket



  • Put the flour in the bowl of a food processor with the 100g butter. Blitz until the mixture resembles fine breadcrumbs, then add 50g of the cheese, 1 tbsp of the thyme leaves, some freshly ground black pepper and 1 tsp salt. Blitz again briefly to combine. Add 2-3 tbsp cold water, and pulse again until it comes together into a dough. If you don’t have a food processor, do this in a bowl – rub the flour into the butter first, then stir in the remaining ingredients with a knife. Wrap and chill for at least 40 mins.


  • Meanwhile, heat the 25g butter and the olive oil in a large frying pan over a low-medium heat, and cook the onions with a pinch of salt for 40-50 mins, stirring often, until sticky, golden and very soft when pressed with the back of a spoon. If they start to catch, reduce the heat further and add a splash of water. Be patient, as they will take a while to caramelise, but keep your eye on the pan so they don’t burn.


  • Stir in the vinegar, sugar and the anchovies. Keep stirring until the vinegar has evaporated, and the anchovies have dissolved into the onions. Remove from the heat.


  • Heat the oven to 190C/170C fan/gas 5 and roll the pastry out onto a lightly floured work surface to a 3mm thickness. Use the pastry to line a 23cm tart tin (use the rolling pin to help you do this). Trim the edges so they’re just overhanging the sides. Patch the pastry with the offcuts, if needed. Scrunch up a sheet of baking parchment, then open it out again to line the pastry, and fill with baking beans. Bake for 15 mins, remove the parchment and beans, then bake for a further 5-8 mins, or until the pastry looks dry, without any raw spots.


  • Meanwhile, whisk the eggs, cream, remaining thyme and the rest of the cheese together with a pinch each of salt and black pepper. Stir in the caramelised onions. Trim the sides of the pastry using a serrated knife to neaten the edges. Pour the filling into the pastry case and tap the tin gently on the work surface to release any bubbles.


  • Bake the quiche for 25-30 mins on the middle shelf of the oven until lightly golden and set in the middle, with a slight wobble. Leave to cool in the tin for at least 15-20 mins, then slice. To make the salad, whisk the olive oil and vinegar together in a bowl, then toss in the remaining ingredients. Pile the salad on top of the quiche, or serve alongside. If you like, leave the quiche to cool completely, then chill before serving. Will keep in the fridge for up to three days.

What Other Types of Onions Can Be Used in Place of French Onions?

You’re not limited to French onions. You could use red, white, or yellow onions. Even shallots or leeks would work. Just remember, each type imparts a different flavor, so you’re also tweaking the taste.

Are There Any Other Types of Tarts This Pastry Crust Would Work Well With?

Absolutely, you can use this cheesy thyme pastry crust with many other tarts. It’d pair well with a spinach and feta tart, a roasted tomato tart or even a hearty bacon and egg tart.


So, you’ve just made a delectable French Onion Tart with a Cheesy Thyme Pastry! It’s a perfect blend of sweet onions, aromatic thyme and cheesy goodness.

Upside Down Onion and Gruyere Tarts 17

This tart is undeniably a showstopper, whether it’s for a fancy dinner or a casual brunch. Don’t forget to pair it with a crisp white wine or a light salad.

Enjoy the rich, complex flavors of this delightful tart, and remember, good food is best shared with good friends.

192 posts

About author
Meet Sue Perera, the culinary aficionado behind our captivating recipe hub. An imaginative and talented young woman, Sue has an unwavering passion for all things food – especially those aromatic wonders, cinnamon and thyme. Her deep-seated love for these two unique spices inspired the birth of this website, but don't be fooled – her culinary repertoire extends far beyond these two ingredients.
You may also like

Classic Bolognese Sauce

5 Mins read
Ready to master the ultimate pasta sauce? You’re in for a treat. In this guide, we’re exploring classic Bolognese, steeped in rich…

Slow Cooker Chinese Pork Shoulder Recipe

4 Mins read
You’re about to embark on a culinary adventure! This Slow Cooker Chinese Pork Shoulder recipe will transport you right to the heart…

Orange Thyme Jam

5 Mins read
You’re about to discover a unique blend of flavors with this homemade orange thyme jam! It’s more than just a spread for…