Vegetarian Cottage Pie

Ingredients
• 2tbsp olive oil
• 1 red onion, chopped
• 200g carrots, finely diced
• 1 stick celery, finely diced
• 250g chestnut mushrooms, chopped
• 400g can Chopped Tomatoes
• 1tbsp tomato puree
• Sprig fresh cut thyme, 1tbsp leaves chopped
• 400g can Green Lentils, drained and rinsed
• 300g sweet potato (peeled weight), cut into even-size pieces
• 300g potato (peeled weight), cut into even-size pieces
• 50g reduced-fat creme fraiche
• 
  
• 
  
• Steps
• 
  
• Preheat the oven to 200C/ 180C Fan/Gas 6. Heat the oil in a pan and cook the onion over a medium heat until soft. Add the carrots and celery, and stir well. Cover and cook over a low heat, stirring occasionally, for 5 minutes. Add the mushrooms and cook, stirring occasionally, until the juices run. Increase the heat and cook, stirring often, until the juices evaporate. Add the tomatoes, tomato puree, thyme and lentils and simmer, stirring occasionally with a spoon, for 10 minutes. Transfer the mixture to a baking dish. Cook the sweet potatoes and potatoes until tender. Drain and mash with the creme fraiche. Put on top of the mushroom and lentil mixture. Bake for 20 minutes.