- 1 package of thawed puff pastry
- 4 tbls of salted butter
- 2 tbls of olive oil
- 2 ½ cups of cremini mushrooms, sliced
- 1 medium yellow onions, diced
- 2 garlic cloves, minced
- 2 tbls of fresh thyme, plus more for garnish
- 1 tsp of Fleischmann's® Cornstarch, mixed with 2 tsps of cold water
- 1 tbls of butter
- 1 tbls of balsamic vinegar
- ½ cup of gruyere cheese, grate
- 1 egg, lightly beaten with 1 tsp of water
- salt and pepper to taste
- Preheat oven to 400°F.
- In a large pan over medium heat, heat 2 tbls of olive oil. Add the diced onions and cook until golden and soft (about 10-15 minutes).
- Stir in salt and add sliced mushrooms. Cook together until the mushrooms are tender and caramelized, about 10 minutes.
- Stir cornstarch slurry and cook until thickened (approx 2 minutes).
- Add in butter, garlic, thyme and balsamic vinegar and cook for another 2 minutes. Remove from heat and set aside.
- Remove the puff pastry from the fridge. Cut into 7cm squares. Score 1 ½ cm from the 4 edges of each square (do not cut right through the pastry).
- Spoon mushroom mixture within the scored areas of each square and top lightly with cheese.
- Brush edges with egg mixture.
- Bake at 400° F for 12-16 minutes or until golden brown.
- Cool on wire rack and garnish with more fresh thyme and season to taste.
- Let cool and enjoy!