Savory Caramelized Onion and Zucchini Quiche

Name: Savory Caramelized Onion and Zucchini Quiche
Prep time: 20 min
Cook time: 40 min
Total time: 1 h
Yield: 8 servings
Ingredients: 1 1/4 cups all-purpose flour; 1/2 teaspoon salt; 1/2 cup unsalted butter, cold and cubed; 3-4 tablespoons ice water; 2 tablespoons olive oil; 2 large onions, thinly sliced; 1 medium zucchini, thinly sliced; 4 large eggs; 1 cup heavy cream; 1 cup shredded cheese (Swiss or Gruyère); Salt and pepper to taste; Fresh thyme (optional, for garnish)

Highlighted under: Family Comfort Meals

I absolutely adore making this Savory Caramelized Onion and Zucchini Quiche, especially when I have some fresh garden vegetables at hand. The sweetness of the caramelized onions beautifully complements the tender zucchini, creating a rich and savory filling that is simply irresistible. I find that using a homemade crust gives it that extra special touch, but store-bought works in a pinch. This quiche is perfect for brunch or a light dinner, and it always impresses my guests!

Created by

Lina

Last updated on 2026-01-17T15:18:28.062Z

Cooking often gives me unexpected joy, especially when I tweak the traditional recipes. Recently, I experimented with this quiche, playing with the filling ingredients until I landed on the divine combination of caramelized onions and zucchini. The key is to let the onions really caramelize; the depth of flavor adds layers that elevate the dish from basic to extraordinary.

What I love most is the creamy egg filling that binds it all together. I’ve learned that using a mix of eggs and cream results in a silkier texture. Pair it with a fresh salad, and you have a well-rounded meal that will both satisfy and impress.

        Why You'll Love This Quiche
        Delicately sweet caramelized onions that enhance the overall flavor
A flaky crust that perfectly cushions the creamy filling
Versatile enough to be enjoyed warm or cold

      

Mastering the Crust

The crust is the backbone of your quiche, and using cold ingredients is essential for achieving that flaky texture. When mixing the cold cubed butter into the flour, aim for pea-sized pieces to ensure a good balance of flakiness and tenderness. To avoid overworking the dough, mix until just combined and consider using a pastry cutter for best results. If you're short on time, a high-quality store-bought pie crust can save the day, but I highly recommend making your own for that homemade touch.

Chilling the crust for at least 30 minutes is a crucial step. This not only firms up the butter, helping it to create steam while baking, but it also prevents shrinkage during the baking process. If you want to make the crust ahead of time, it can be refrigerated for up to 2 days or frozen for a month. Just remember to let it thaw in the fridge overnight before rolling it out again.

Caramelizing the Onions

Caramelizing onions isn’t just about color; it’s about developing a deep, sweet flavor that balances beautifully with the zucchini. Start with sliced onions in a well-oiled skillet over medium heat. Stir often until the onions turn golden brown, which usually takes around 15 to 20 minutes. If your onions start sticking, add a splash of vegetable broth or water to deglaze the pan and prevent burning.

Adding zucchini to the onions introduces a lovely textural contrast. While cooking for an additional 5 minutes, keep an eye on the zucchini to ensure it retains a bit of crispness. Overcooking can turn it mushy, which you want to avoid for a well-structured quiche. Feel free to enhance the caramelized mixture with a splash of balsamic vinegar for added depth.

Customizing Your Quiche

This quiche is extremely versatile, allowing you to adjust the filling based on what you have on hand. If you want to switch things up, try adding cooked bacon or spinach for a heartier version. For a gluten-free option, consider using a gluten-free pie crust or making a crustless quiche by skipping the crust entirely—just grease the pan well to prevent sticking.

When it comes to cheese, Swiss and Gruyère are traditional, but feel free to experiment with feta, goat cheese, or cheddar for a different flavor profile. If you’re looking to lighten the dish, you can substitute half of the heavy cream with milk, but be mindful that it may result in a less creamy texture. Lastly, consider adding fresh herbs into the filling for an extra layer of flavor; fresh thyme pairs beautifully with the other ingredients!

Ingredients

Gather these ingredients to make your perfect quiche:

For the Crust

1 1/4 cups all-purpose flour
1/2 teaspoon salt
1/2 cup unsalted butter, cold and cubed
3-4 tablespoons ice water

For the Filling

2 tablespoons olive oil
2 large onions, thinly sliced
1 medium zucchini, thinly sliced
4 large eggs
1 cup heavy cream
1 cup shredded cheese (Swiss or Gruyère)
Salt and pepper to taste
Fresh thyme (optional, for garnish)

Your ingredients are now ready for preparation!

Instructions

Follow these steps to create your delicious quiche:

Prepare the Crust

In a mixing bowl, combine the flour and salt. Add the cold cubed butter and mix until crumbly. Gradually add ice water, mixing until the dough comes together.

Press into a pie dish and refrigerate for at least 30 minutes.

Caramelize the Onions

Heat olive oil in a skillet over medium heat. Add sliced onions and cook, stirring occasionally, until they are golden and caramelized, about 15-20 minutes. Add zucchini and cook for an additional 5 minutes.

Make the Filling

In a bowl, whisk together eggs, heavy cream, salt, and pepper. Stir in the caramelized onion and zucchini mixture, along with the shredded cheese.

Assemble and Bake

Preheat oven to 375°F (190°C). Pour the filling into the chilled crust and bake for 30-35 minutes, or until the quiche is set and the top is lightly golden. Let it cool slightly before slicing.

Enjoy your homemade quiche fresh out of the oven!

Pro Tips

For extra flavor, consider adding cooked bacon or ham to the filling. You can also substitute other vegetables like spinach or bell peppers based on your preference.

Serving Suggestions

This Savory Caramelized Onion and Zucchini Quiche is delightful on its own, but consider serving it with a simple mixed greens salad drizzled with lemon vinaigrette for a refreshing contrast. You can also top it with a dollop of crème fraîche or a sprinkle of extra herbs for a gourmet touch. Serve it warm or at room temperature, making it an ideal dish for any gathering.

If you're planning to serve it for brunch, accompany the quiche with some seasonal fruit or an array of pastries for a beautiful spread. It’s also excellent as a light dinner option paired with a crisp white wine, such as Sauvignon Blanc, which elevates the flavors of the quiche.

Make-Ahead Tips

One of the best features of this quiche is that it keeps well, making it a fantastic make-ahead dish. You can prepare the entire quiche and refrigerate it for up to two days before baking, ensuring that the flavors meld beautifully. Just cover it securely with plastic wrap or foil to prevent it from absorbing any odors from the fridge.

If you're short on time, consider assembling the quiche and freezing it before baking. Wrap it tightly in plastic wrap and foil to prevent freezer burn. When ready to bake, simply thaw it in the refrigerator overnight and bake as directed. This way, you can enjoy a comforting meal with minimal effort on busy days.

Storage and Reheating

Leftover quiche can be stored in an airtight container in the refrigerator for up to 4 days. To reheat, simply place slices in a microwave-safe dish and heat for about 1 to 2 minutes, or until warmed through. Alternatively, for a crispier texture, reheat slices in the oven at 350°F (175°C) for about 10-15 minutes, until the edges are slightly crispy and it’s heated completely.

If necessary, you can also freeze the cooked quiche for up to 2 months. Wrap individual slices tightly in plastic wrap and place them in a freezer-safe bag. When you’re ready to enjoy some, let it thaw in the refrigerator overnight and then reheat as desired. This makes for quick meals when you're on the go!

Questions About Recipes

→ Can I use a store-bought crust?

Absolutely! A store-bought crust will save you time and still result in a delicious quiche.

→ How long can I store leftovers?

Leftovers can be stored in the fridge for up to 3 days in an airtight container.

→ Can I freeze this quiche?

Yes, you can freeze the unbaked quiche. Just wrap it well and bake it directly from frozen when you’re ready to enjoy.

→ What cheese can I substitute?

You can substitute with feta, cheddar, or any cheese of your choice that melts well.