- Prepare the Onion Mixture:
- In a large skillet, melt the butter over medium heat.
- Add the chopped onion and cook, stirring frequently, until the onions are soft and caramelized, about 10-15 minutes.
- Stir in the thyme leaves and cook for an additional minute. Remove from heat and let cool slightly.
- Prepare the Sausage Filling:
- In a large bowl, combine the sausage meat with the cooled onion mixture.
- Add the Dijon mustard, grated cheese, breadcrumbs, and season with salt and pepper. Mix until well combined.
- Assemble the Sausage Rolls:
- Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.
- Roll out the puff pastry on a lightly floured surface. Cut it into rectangles, about 3 inches by 6 inches (8 cm by 15 cm).
- Place a portion of the sausage mixture along one edge of each pastry rectangle.
- Roll the pastry over the sausage filling to form a log shape, sealing the edges by pressing them together with a fork or your fingers.
- Place the sausage rolls seam-side down on the prepared baking sheet.
- Prepare for Baking:
- Brush each sausage roll with the beaten egg for a golden, shiny finish.
- If desired, sprinkle the tops with sesame seeds or poppy seeds for extra texture and flavor.
- Bake:
- Bake the sausage rolls in the preheated oven for 20-25 minutes, or until they are golden brown and puffed up.
- Cool and Serve:
- Allow the sausage rolls to cool slightly before serving. They are delicious either warm or at room temperature.
Enjoy these French Onion Sausage Rolls as a flavorful appetizer, snack, or even as part of a meal!