Puff pastry with cheese and sausage

Ingredients:

• 120 g sausage, sliced
• 1 sheet frozen puff pastry (half a 0.5 kg package), thawed
• 2 tsp hot mustard + extra for serving
• 170 g of curdled cheese (or semi-skimmed mozzarella, cut into pieces)
• 1 large egg, lightly beaten
• Flaked salt

Preparation:

1. Preheat oven to 220°C. Line a rimmed baking sheet with parchment paper.
2. In a medium nonstick skillet over medium-high heat, cook the sausage, stirring, until browned, 4 to 6 minutes; then set aside to cool.
3. Place the puff pastry on the prepared baking sheet; spread mustard on top, leaving a 2.5 cm border. Place the sausage on one half of the pastry and sprinkle with the cheese curds. Fold the other half of the pastry over the filling and crimp the edges with a fork to seal. Freeze for about 45 minutes.
4. Brush the dough with beaten egg and sprinkle with flaky salt. Make 4 slits in the surface of the dough to allow steam to escape. Bake until the dough is puffed and golden brown, about 30 minutes. Cool for 20 minutes, then transfer to a cutting board and slice. Serve warm or at room temperature with mustard.