1. Add lentils to a large saucepan and add the vegetable stock, bring to the boil and leave to simmer for 20-25 minutes. The lentils should be softened, but don’t need to be thoroughly cooked all the way through.
2. While the lentils are cooking, add the roughly chopped onion and garlic to a non-stick frying pan and cook for 3-5 minutes until fragrant. Add the roughly chopped mushrooms and dried thyme and cook for a further 4-5 minutes.
3. When the lentils are ready, drain any excess water (if any is present) and add the lentils and the vegetables to a food processor. Pulse a few times, then add in the pecans and pulse again. Stop when the ingredients are combined enough to hold their shape when moulded, but still have some texture. Stir in the mustard.
4. Put the mixture in the fridge for 30 minutes to chill before shaping. At this time, remove the pastry sheet from the fridge to give it time to become room temperature before using it.
5. After 30 minutes, remove the lentil/ vegetable mix and divide into 6 equal sized servings and shape them into ‘sausages’.
6. Cut the pastry sheet all the way down through the centre, lengthways. Place each sausage down the middle of each length of pastry.
7. Roll the pastry around the sausage, brush with olive oil to seal the edges.
8. Cut each piece into approximately 6 sausage rolls and place on a baking tray. Brush the tops with the rest of the oil (optional). Bake for 20 mins or until golden (or not if using GF pastry) and cooked through.

Serve and enjoy!