Layered Potato, Lentil and Vegetable Casserole with a herb crust

1. Heat the oil in a medium saucepan. Add the onion, garlic and tomatoes and cook gently until softened. 
2. Add the vegetable stock, celery, carrots and baby marrows. Stir through, bring to the boil and cook for about 10 minutes.
3. Add the tomato sauce, sugar, herbs and seasoning and stir to combine. Reduce the heat to a simmer.
4. Add the mushrooms, peas and lentils and cook for about 30 minutes until the vegetables are soft and the sauce is moist
5. Grease an ovenproof casserole dish and place ¼ of the sliced potatoes in the bottom of the dish.  Spoon over 1/3 of the vegetables and season with salt and black pepper. Repeat twice ending with a layer of sliced potato.
6. Preheat the oven to 200°C.
7. Make the herb crust: in a small bowl, combine the mixed herbs and paprika. Sprinkle over the top layer of potato, and drizzle with olive oil.
8.  Bake for about 20 minutes, until crisp and bubbling.

Serve with a fresh green salad.