Step-by-Step Instructions

• Preheat your oven to 400°F (200°C) and line a baking tray with parchment paper.
• In a large skillet, melt 2 tablespoons of unsalted butter with 1 tablespoon of olive oil over medium heat. Add the finely sliced onions and sauté for about 20 minutes until caramelized and golden brown.
• Add 2 minced garlic cloves, 1 teaspoon of fresh thyme leaves, and 1 teaspoon of Worcestershire sauce to the onions. Sprinkle with salt and pepper to taste, then sauté for an additional 2 minutes. Remove from heat and let cool.
• In another skillet, cook 1 pound of Italian sausage over medium heat until browned and fully cooked. Drain excess fat and let cool slightly.
• In a mixing bowl, combine the cooled sausage with the onion mixture and 1 cup of shredded Gruyère cheese until well mixed.
• Flour a clean surface and roll out the thawed puff pastry sheets.
• Cut the pastry sheets into rectangles measuring approximately 4 inches by 6 inches.
• Place a spoonful of filling onto one end of each pastry rectangle, leaving space at the edges.
• Fold the other end of the pastry over the filling and seal the edges with a fork.
• Arrange the rolls on the baking tray and brush the tops with beaten egg.
• Bake for about 20-25 minutes until puffed up and golden brown.
• Remove from the oven and let cool slightly before serving warm.