Savory Onion Tart for Lovers

Name: Savory Onion Tart for Lovers
Prep time: 20 min
Cook time: 40 min
Total time: 1 h
Yield: 8 servings
Ingredients: 1 pre-made pastry crust; 4 large onions (mix of sweet and red); 2 tablespoons olive oil; 2 tablespoons unsalted butter; Salt and pepper to taste; 1 cup Gruyère cheese, grated; 1/2 cup goat cheese, crumbled; 3 large eggs; 1 cup heavy cream; 1 teaspoon fresh thyme, chopped

Highlighted under: Classic Comfort Cooking

I absolutely adore making this Savory Onion Tart for Lovers! It's a recipe that never fails to impress, whether I'm serving it at a cozy dinner for two or a festive gathering. The rich, caramelized onions combined with a flaky pastry create an irresistible dish that has everyone asking for seconds. I particularly enjoy using a mix of sweet and red onions for added depth of flavor. Trust me, this tart is sure to win hearts and taste buds alike, making it the perfect addition to any occasion.

Created by

Sophia

Last updated on 2026-01-17T16:18:27.838Z

When I first crafted this Savory Onion Tart, I wanted to create a dish that showcased the sweet, comforting flavors of caramelized onions. As the onions cook down, they develop a deep, golden color and a rich sweetness that truly elevates the dish. I've experimented with different cheese combinations, and I find that a blend of Gruyère and goat cheese brings an incredible creaminess that perfectly complements the tart's texture.

If you want to get that perfect, flaky crust, I recommend chilling the dough before baking; this little step makes a noticeable difference! Pair it with a light salad, and you’ve got a beautiful meal that feels special yet is simple enough for any weeknight dinner.

        Why You'll Love This Recipe
        Caramelized onions with a hint of sweetness provide incredible depth of flavor.
A buttery, flaky pastry that complements the savory filling perfectly.
Versatile enough to be served as an appetizer, main dish, or even brunch!

      

The Art of Caramelizing Onions

Caramelizing onions is a skill that truly enhances the flavors in this Savory Onion Tart. Begin by slicing your onions evenly; this ensures they caramelize uniformly. Use a mix of sweet and red onions for a balance of flavor and color. Cooking over medium heat allows the natural sugars in the onions to develop gradually. Be patient—this process takes about 25 minutes but watch for them to turn a deep, rich golden brown and develop a nice, sweet aroma.

Keep an eye on your skillet and stir the onions occasionally to prevent burning. If they start to stick or brown too quickly, lower the heat. You can also deglaze the pan with a splash of white wine or balsamic vinegar for an added layer of flavor, scraping up any golden bits stuck to the bottom, which contributes to the tart’s depth.

Choosing the Right Cheese

The cheeses you choose play an essential role in the flavor profile of your tart. Gruyère adds a nutty, creamy richness that harmonizes beautifully with the sweetness of the caramelized onions. If you’re looking for a stronger flavor, consider adding a sharper cheese like aged cheddar or even a blue cheese—but be mindful of balancing it with the goat cheese to avoid overwhelming the dish.

Goat cheese offers a tangy contrast that lightens the richness of the tart. Be sure to crumble it evenly over the onion layer to ensure every bite has a touch of its creamy texture. If you need a dairy-free option, you can substitute with a non-dairy cream and a nut-based cheese, adjusting the seasoning to maintain balance.

Serving and Storing Leftovers

This Savory Onion Tart can be served warm or at room temperature, making it versatile for any occasion. Cut into generous slices for a delightful appetizer, or pair smaller pieces with a fresh green salad for a satisfying brunch. A drizzle of balsamic glaze or a sprinkle of fresh herbs like parsley or chives can add a beautiful finishing touch when serving.

If you have leftovers, you can store them in an airtight container in the refrigerator for up to three days. Reheat in the oven at 350°F (175°C) for about 10-15 minutes until warmed through. For longer storage, the tart freezes well; simply wrap it tightly in plastic wrap and aluminum foil, and it can be frozen for up to two months. Thaw overnight in the refrigerator before reheating to enjoy its full flavor.

Ingredients

For the Tart

1 pre-made pastry crust
4 large onions (mix of sweet and red)
2 tablespoons olive oil
2 tablespoons unsalted butter
Salt and pepper to taste
1 cup Gruyère cheese, grated
1/2 cup goat cheese, crumbled
3 large eggs
1 cup heavy cream
1 teaspoon fresh thyme, chopped

Instructions

Prepare the Onions

In a large skillet, heat the olive oil and butter over medium heat. Add the sliced onions, sprinkle with salt, and cook, stirring occasionally, for about 25 minutes, or until they are caramelized and golden brown.

Assemble the Tart

Preheat your oven to 375°F (190°C). Spread the caramelized onions evenly over the pastry crust. Sprinkle the Gruyère and goat cheese on top.

Whisk together the eggs, cream, thyme, pepper, and pour the mixture over the onions and cheese.

Bake the Tart

Bake the tart in the preheated oven for 30-35 minutes, or until the filling is set and the top is lightly golden. Allow to cool for a few minutes before slicing.

Pro Tips

For an extra touch, try adding some sautéed mushrooms or fresh herbs to the filling for added flavor. This tart is also delicious served warm or at room temperature, making it a great choice for entertaining.

Variations to Try

Feel free to customize the tart by adding other ingredients that complement the onion base. For instance, sautéed mushrooms, spinach, or roasted red peppers can add depth and color to the filling. Just remember that adding moisture-rich vegetables may require you to adjust your cooking time to ensure the tart doesn’t become soggy.

You can also experiment with different herbs. While thyme is classic, fresh basil or rosemary can bring a new flavor dimension. If using dried herbs, remember that they are more potent, so use about one-third of the amount compared to fresh.

Troubleshooting Common Issues

If your tart filling seems too runny after baking, it may be due to excess moisture from the onions or cheese. For future attempts, try cooking the onions longer to allow more moisture to evaporate and consider draining any liquid from the cheese before adding it to the tart. Adjusting the oven temperature slightly higher can also help set the filling more firmly.

Sometimes, the pastry crust may turn out soggy. To combat this, you can blind bake the crust for about 10-15 minutes before adding the filling. This pre-baking allows the crust to firm up and creates a barrier between the dough and the moist filling.

Scaling the Recipe

This Savory Onion Tart is easily scalable, making it a fantastic choice for larger gatherings. To double the recipe, simply use a larger tart pan and increase your baking time by the same ratio. Be cautious not to overfill the pan, as this can cause uneven cooking and prevent the filling from setting properly.

If you want individual servings, consider making mini tarts in a muffin tin. Cut the pastry crust into circles and press them into the muffin cups, then fill them with the onion mixture and adjust the baking time to about 20-25 minutes. This approach is not only charming but also makes for easy serving.

Questions About Recipes

→ Can I use a homemade pastry crust?

Absolutely! A homemade pastry crust adds a wonderful touch and can be tailored to your personal taste.

→ What can I serve with the onion tart?

This tart pairs beautifully with a light mixed greens salad, drizzled with a simple vinaigrette.

→ Can I make this dish ahead of time?

Yes, you can prepare the tart a day in advance. Just bake it, let it cool, and store it in the refrigerator. Reheat before serving.

→ What if I don't like goat cheese?

No problem! You can substitute with ricotta or feta for a different but equally delicious flavor.