Step 1

Preheat oven to 200C/180C fan-forced. Line 2 baking trays with baking paper.

Step 2

Heat the oil in a large frying pan over medium heat. Add the onion. Cook, stirring often, for 4-5 minutes or until soft. Add the garlic, Vegemite and chilli (if using) and cook, stirring, for 30 seconds or until aromatic. Add the mushrooms and cook, stirring often, for 5 minutes or until soft and the liquid has evaporated. Add the sweet potato and cook, stirring, for 2 minutes or until softened. Stir in the lentils and thyme. Season. Transfer to a large heatproof bowl. Set aside, stirring often, for 15 minutes to cool. Stir in the cheese.

Step 3

Cut each pastry sheet in half. Place one quarter of the sweet potato mixture in a log shape along one long edge of the pastry. Brush the opposite edge with egg. Roll up tightly to enclose. Repeat with the remaining pastry and filling. Cut each roll into 4 pieces and place, seam-side down, on the prepared trays.

Step 4

Brush the pastry with egg and use a sharp knife to score lines into the top of the pastry. Bake for 25 minutes or until golden brown. Serve with tomato relish or sauce.