Balsamic Onion Mushroom Blue Cheese Tarts

Elevate your appetizer game with these irresistible Balsamic Onion Mushroom Blue Cheese Tarts—a delightful combination of buttery puff pastry, sweet caramelized onions, earthy mushrooms, and rich, tangy blue cheese. This recipe strikes the perfect balance of flavors, with savory and sweet notes tied together by the subtle complexity of fresh thyme and balsamic vinegar. The golden, flaky pastry base is easy to prepare and beautifully crisped with a simple egg wash, making these tarts as elegant as they are delicious. Perfect for entertaining or as a sophisticated snack, these gourmet-inspired tarts are ready in just about an hour and are sure to impress at any occasion.

Nutriscore Rating: 54/100

Prep Time:20 mins

Cook Time:40 mins

Total Time:60 mins

Servings: 6

Ingredients

• 1 package puff pastry sheet
• 2 tablespoons butter
• 1 tablespoon olive oil
• 2 large yellow onion
• 2 tablespoons balsamic vinegar
• 1 teaspoon brown sugar
• 2 cloves garlic
• 8 ounces mushrooms
• 1 teaspoon fresh thyme
• 4 ounces blue cheese crumbles
• 1 egg
• 1 tablespoon water
• 0.5 teaspoon salt
• 0.25 teaspoon black pepper

Directions

Step 1

Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.

Step 2

Thaw the puff pastry sheet according to the package instructions. Once thawed, unfold and cut into 6 equal squares or rectangles. Transfer the pieces to the prepared baking sheet and set aside.

Step 3

In a medium skillet, heat 1 tablespoon of butter and the olive oil over medium heat.

Step 4

Thinly slice the onions and add them to the skillet. Cook for 10-12 minutes, stirring occasionally, until they become soft and begin to caramelize.

Step 5

Stir in the balsamic vinegar and brown sugar. Cook for an additional 2-3 minutes until the mixture is sticky and glossy. Remove the onions from the pan and set them aside.

Step 6

Thinly slice the mushrooms and mince the garlic.

Step 7

In the same skillet, melt the remaining 1 tablespoon of butter. Add the garlic and sauté for 1 minute until fragrant.

Step 8

Add the mushrooms and cook for 5-7 minutes until tender and any liquid released has evaporated. Stir in the fresh thyme, salt, and black pepper. Remove mushrooms from heat.

Step 9

Use a sharp knife to score a ½-inch border around the edges of each puff pastry square. Be careful not to cut all the way through. Prick the center of each square several times with a fork.

Step 10

Divide the caramelized onions and mushrooms evenly among the squares, spreading them within the scored borders.

Step 11

Top each tart with blue cheese crumbles, distributing evenly.

Step 12

In a small bowl, whisk together the egg and water to make an egg wash. Brush the edges of the pastry with the egg wash to promote golden-brown crisping.

Step 13

Bake the tarts in the preheated oven for 20-25 minutes or until the pastry is puffed and golden.

Step 14

Remove from the oven and allow tarts to cool slightly before serving. Garnish with additional thyme if desired.

Nutrition Facts

Serving size	(1342.1g)

Amount per serving	% Daily Value*
Calories	4186.2

Total Fat 291.1g	0%
Saturated Fat 89.6g	0%
Polyunsaturated Fat 7.6g
Cholesterol 342.4mg	0%
Sodium 5750.4mg	0%
Total Carbohydrate 305.5g	0%
Dietary Fiber 19.8g	0%
Total Sugars 39.2g
Protein 80.2g	0%

Vitamin D 68.4IU	0%
Calcium 790.0mg	0%
Iron 17.1mg	0%
Potassium 2453.0mg	0%

*The % Daily Value tells you how much a nutrient in a serving of food contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.

Source of Calories

Fat: 62.9%

Protein: 7.7%

Carbs: 29.4%