Caramelized Onion & Cheese Tartlets are savory bite-sized delights featuring golden puff pastry filled with sweet, slow-cooked onions and melted cheese. These elegant tartlets make for a perfect appetizer, party snack, or brunch addition, combining rich flavors and beautiful presentation.

Why You’ll Love This Recipe

These tartlets are a perfect balance of flavor and texture. The buttery, flaky crust pairs beautifully with the sweetness of caramelized onions and the savory sharpness of cheese. They are simple to make, easy to serve, and versatile enough for both casual and formal gatherings.

Ingredients

(Tip: You can find the complete list of ingredients and their measurements in the recipe card below.)

Puff pastry sheets, thawed
Yellow or sweet onions, thinly sliced
Olive oil or butter
Balsamic vinegar (optional, for depth of flavor)
Sugar (optional, for enhanced caramelization)
Shredded Gruyère, mozzarella, or cheddar cheese
Salt and pepper
Fresh thyme or parsley for garnish

Directions

Preheat oven to 375°F (190°C). Lightly grease or line a muffin tin or baking tray.
In a skillet over medium heat, add oil or butter. Cook sliced onions slowly until golden brown and caramelized, about 25–30 minutes. Stir occasionally. Add balsamic vinegar or sugar if using.
Roll out puff pastry and cut into circles or squares to fit your tin or preferred shape.
Place pastry into the tin or on the tray. Spoon in a layer of caramelized onions and top with shredded cheese.
Bake for 15–20 minutes, or until pastry is golden and cheese is melted and bubbly.
Garnish with fresh herbs and serve warm.

Servings and Timing

Servings: 12 tartlets
Preparation Time: 20 minutes
Cooking Time: 30 minutes (including caramelizing onions)
Baking Time: 15–20 minutes
Total Time: Approximately 50–60 minutes

Variations

Add crumbled goat cheese or blue cheese for a tangier flavor.
Mix in sautéed mushrooms or roasted red peppers.
Use phyllo dough instead of puff pastry for an extra flaky crust.
Serve with a drizzle of honey or fig jam for a sweet-savory twist.

Storage/Reheating

Store in an airtight container in the refrigerator for up to 3 days.
Reheat in the oven at 350°F (175°C) for 5–10 minutes to restore crispiness.
Not recommended for freezing after baking, but the unbaked tartlets can be frozen and baked fresh.

FAQs

Can I make these ahead of time?

Yes, caramelize the onions and prep the tartlets in advance. Bake just before serving.

What cheese works best?

Gruyère and sharp cheddar are ideal, but mozzarella or fontina also work well.

Can I use store-bought puff pastry?

Absolutely. Frozen puff pastry sheets are convenient and bake beautifully.

How do I keep the pastry from getting soggy?

Cool the caramelized onions slightly before assembling and avoid excess liquid.

Can I serve these cold?

They’re best warm, but still flavorful at room temperature for parties.

Can I make them in a mini muffin tin?

Yes, for bite-sized appetizers. Just adjust the baking time slightly.

Do I need to blind bake the pastry?

No blind baking is necessary when using puff pastry for these tartlets.

What herbs pair well with this?

Fresh thyme, rosemary, or parsley complement the flavors nicely.

Can I add meat?

Yes, diced bacon or pancetta pairs wonderfully with the onion and cheese.

Are they vegetarian?

Yes, if you use vegetarian-friendly cheese and no meat additions.

Conclusion

Caramelized Onion & Cheese Tartlets are elegant, flavorful, and irresistibly crisp. With their sweet-savory onion base and golden cheese topping, they make a perfect addition to any menu — whether you are hosting a holiday gathering or just want a refined snack. Easy to prepare and always impressive, they are sure to be a crowd-pleaser.

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These Caramelized Onion & Cheese Tartlets are buttery, flaky, and packed with rich, sweet onions and melty cheese. Perfect as an appetizer, party bite, or fancy side dish, they’re a crowd-pleasing savory pastry. Keyword: Caramelized Onion & Cheese Tartlets

Author: Emma Harper
Prep Time: 20 minutes
Cook Time: 25 minutes
Total Time: 45 minutes
Yield: 8–10 tartlets
Category: Appetizer, Snack
Method: Baking
Cuisine: French-Inspired

Instructions

Preheat oven to 400°F (200°C). Line a baking sheet with parchment paper.
Heat olive oil and butter in a skillet over medium-low. Add onions, sugar, salt, and pepper. Cook 20–25 minutes until golden and caramelized, stirring occasionally.
Roll out puff pastry and cut into circles or squares (about 3-inch diameter).
Place on baking sheet. Score a smaller circle inside each piece without cutting through, to create a border.
Fill center with caramelized onions and top with cheeses.
Brush pastry edges with beaten egg.
Bake for 15–18 minutes until puffed and golden.

Garnish with fresh herbs and serve warm.

Notes

Use mini muffin tins for bite-sized versions.
Add cooked bacon or roasted garlic for extra depth.

Delicious warm or at room temp for entertaining.