Combine sweet, caramelized onions, decadent mushrooms and rich goat cheese in this delicious tart appetizer – perfect for holiday entertaining.
Recipe courtesy of Jennifer of Savory Simple.
- 1 tablespoon extra-virgin olive oil
- 2 large or 3 small yellow onions, sliced thin
- 6 ounces mushrooms (I used baby bellas), coarsely chopped
- 1 sprig thyme
- 1 tablespoon balsamic vinegar
- 1 sheet puff pastry
- 1/4 cup goat cheese, crumbled
- 1/4 teaspoon kosher salt
- 1 egg, beaten
- Heat 1 tablespoon of olive oil on low in a large skillet. Have a measuring cup full of water on standby. Add the onions to the skillet along with a pinch of salt. Sweat the onions, stirring, until they begin to caramelize. Turn up the heat to medium-low. Once a brown glaze has formed on the bottom of the skillet, pour approximately 2 tablespoons of water into the pan to deglaze and use a spatula to scrape up the brown bits and stir them into the onions. Repeat this glazing and deglazing process until the onions have been thoroughly caramelized and taste bitter and only slightly sweet, approximately 25-35 minutes. Use more or less water as needed. Set the caramelized onions aside.
- Clean the skillet and place back on the stovetop. Add the mushrooms, thyme leaves and a pinch of salt. Heat the mushrooms over low heat until they begin to release water. Turn the heat up to medium-low and cook the mushrooms, stirring frequently, until the water has mostly evaporated. Add the balsamic vinegar and continue stirring for another 2 minutes. Set the mushrooms aside.
- Preheat oven to 400 degrees F and line a baking sheet with parchment paper.
- On a lightly floured surface, roll the puff pastry sheet to approximately 9×10 inches. Use a fork to poke several holes throughout the dough (this will help prevent air bubbles). Spread the caramelized onions evenly on top of the dough, leaving a small border around the ends. Top with the mushrooms, followed by the goat cheese. Sprinkle the salt on top.
- Use a pastry brush to add egg wash to the border of the tart (it will give the dough some color). Place the tart in the oven and bake for 20-25 minutes, until the puff pastry is cooked through. Check the tart periodically while it’s cooking to make sure air bubbles are not forming. If one appears, carefully use the tip of a knife or fork to deflate the dough, then allow it to finish cooking.
- Allow to cool for several minutes, and then cut and serve.