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Caramelized onion brie tarts are a delicious appetizer featuring rich, creamy brie cheese and sweet, golden-brown caramelized onions served on crisp, bite-sized crispy puff pastry.
These tarts are our absolute favorite indulgent appetizer for parties and addition to picnics. Brie cheese works as the base for the sweet and succulent caramelized onions and the brie is the boat that holds it all together. Once you have tried these you will be hooked!
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At Sweet C’s, I add lots of tips in all of my recipes – because I am a home cook without any formal training, and I find I am more confident making dishes when I understand why it works, and what each ingredient means to the flavor of a recipe. My goal is for even the most beginner home cook to feel empowered in the kitchen.
Table of Contents
How to Make Sweet Onion Brie Bites
First assemble the following ingredients:
- Puff pastry (3 sheets) – Puff pastry offers a light, flaky texture with a rich, buttery flavor, serving as a delicate and crisp foundation.
- Yellow onions (2) – Yellow onions provide a robust, slightly sweet flavor that deepens and sweetens further when cooked, adding a hearty depth to the tarts.
- Salted butter (2 tbsp) – Salted butter imparts a creamy, rich taste with a subtle hint of saltiness, enhancing the flavors of ingredients.
- Balsamic vinegar (1 ½ tbsp) – Balsamic vinegar adds a complex, slightly sweet, and tangy flavor with a hint of woodsy richness, ideal for balancing and enhancing savory tarts.
- Sea salt (? tsp) – Sea salt offers a clean, straightforward saltiness that enhances the natural flavors of ingredients without the bitterness of iodized salt.
- Brown sugar (½ tsp) – Brown sugar contributes a deep, molasses-like sweetness, adding a rich, caramelized flavor to the onions.
- Wheel of Brie Cheese (8oz) – Brie cheese is known for its creamy, rich texture and mild, buttery flavor with earthy undertones, making it a versatile and luxurious addition to these tarts.
Once you have assembled the ingredients, use this Method:
Prep
Preheat the oven to 400 degrees F. Line a baking sheet with parchment paper or a silicone nonstick baking sheet. Set aside.
Cook Onions
Melt the butter in a small saucepan over medium heat. Add the onions and cook, stirring occasionally, for at least 20 minutes until deeply brown and they smell sweet. Add the balsamic vinegar, salt, and brown sugar. Cook for another 5 minutes to reach a consistency similar to jam. Set aside to cool.
Cut Pastry
Cut the puff pastry into squares. Use a knife, cut an L shape on the bottom and right hand side. Cut another upside down L shape on the other side of each piece.
Boat Pastry
Gently place the cut corner over the pastry so it rests on the opposite side. Do the same with the other side. This should have a boat-like effect where each tart now has an outer edge to hold the filling in. Brush egg wash around the outside.
Add Cheese
Place a piece of brie into each tart square.
Top and Bake
Add some caramelized onion on top of the cheese. Place the tarts on the prepared baking sheet then bake for about 20 minutes or until golden brown. Remove the tarts from the oven, some cheese may leak out during cooking which is fine. Enjoy!
Tips and Tricks for Perfect Onion Brie Tarts
Selecting Ingredients: Use good quality puff pastry for the best results. For the onions, choose varieties like Vidalia or Walla Walla, known for their sweetness. The brie should be ripe but firm, making it easier to slice and melt beautifully without becoming too runny.
Caramelizing Onions: Patience is key when caramelizing onions. Cook them slowly over low heat to bring out their natural sugars without burning. Adding a pinch of sugar can accelerate this process, but be careful not to overdo it. Stir frequently to ensure even caramelization.
Seasoning: Enhance the flavors with a sprinkle of fresh thyme or rosemary over the tarts before baking. A light dusting of black pepper can add a subtle heat.
Baking to Perfection: Preheat your oven and bake the tarts until the pastry is golden and puffed, and the brie is just melted. Overbaking can cause the cheese to become too runny and the pastry too hard.
Serving: Serve these tarts warm for the best taste and texture. However, they are also delicious at room temperature, making them a great make-ahead appetizer.
Adding a Glaze: For an extra touch of flavor and shine, brush the caramelized onions with a bit of balsamic glaze before baking.
Variations: Feel free to add other ingredients like chopped nuts for crunch, a sprinkle of blue cheese for a sharper flavor, or even some crispy bacon bits for a savory twist.
Storing and Reheating: If you have leftovers, store them in an airtight container in the refrigerator. Reheat in the oven or toaster oven to maintain the pastry’s crispness.
FAQs
Yes, you can prepare the caramelized onions in advance and store them in the refrigerator for up to 3-4 days. Assemble and bake the tarts shortly before serving for best results.
Sweet onions like Vidalia or Walla Walla are ideal for caramelizing due to their high sugar content. However, regular yellow onions also work well.
Prick the pastry with a fork before adding toppings, which allows steam to escape and keeps the pastry crisp. Also, avoid overloading the pastry with too much topping.
It typically takes about 30-45 minutes to properly caramelize onions over low heat. The key is to cook them slowly to bring out their natural sweetness without burning them.
Absolutely! Feel free to experiment with additions like chopped nuts, bacon bits, or different herbs for varied flavors.
These tarts are best served warm. However, they can also be enjoyed at room temperature, making them a versatile choice for gatherings.
While brie is a classic choice for its creamy texture, you can use Camembert, goat cheese, or even a sharp cheddar as alternatives.
Store any leftovers in an airtight container in the refrigerator and consume within 2-3 days. Reheat in the oven or toaster oven to maintain the pastry’s crispness.
Try these Appetizers Next
These brie bites are a wonderful accompaniment to Thanksgiving or Christmas dinner table. If you love the flavor combination, try my French Onion Soup or French Onion Chicken next!
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Caramelized Onion Brie Bites
Equipment
Ingredients
- 3 rectangular sheets puff pastry, thawed in refrigerator
- 2 yellow onions, sliced thin
- 2 tbsp salted butter
- 1 ½ tbsp balsamic vinegar
- ⅛ tsp sea salt
- ½ tsp brown sugar
- 1 egg
- 1 tsp water
- 8 oz wheel of brie
Instructions
- Preheat the oven to 400 degrees F. Line a baking sheet with parchment paper or a silicone nonstick baking sheet. Set aside.
- Melt the butter in a small saucepan over medium heat. Add the onions and cook, stirring occasionally, for at least 20 minutes until deeply brown and they smell sweet.
- Add the balsamic vinegar, salt, and brown sugar. Cook for another 5 minutes to reach a consistency similar to jam. Set aside to cool.
- Cut the puff pastry into squares. Use a knife, cut an L shape on the bottom and right hand side. Cut another upside down L shape on the other side of each piece. See process picture.
- Gently place the cut corner over the pastry so it rests on the opposite side. Do the same with the other side. This should have a boat-like effect where each tart now has an outer edge to hold the filling in.
- In a small bowl whisk the egg with about 1 tsp of water till frothy.
- Brush each pastry square with the egg wash.
- Place a piece of brie into each tart square then add some caramelized onion on top of the cheese.
- Place the tarts on the prepared baking sheet then bake for about 20 minutes or until golden brown.
- Remove the tarts from the oven, some cheese may leak out during cooking which is fine. Enjoy!
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
Yum!