lentil and potato bake

Uses mainly storecupboard ingredients. Good for a healthy, warming family dinner/supper.

For 4 people:

 - 4 medium potatoes, peeled and sliced lengthwise
 - about 200g/4oz lentils (any sort, but the small brown ones work best) preferably soaked beforehand
 - 1 large onion
 - 1 tablespoon olive oil
 - couple of carrots, sticks of celery, or any other odd vegetables you've got
 - handful grated cheese
 - 1 teaspoon dried herbs, or 2 teaspoons chopped fresh ones if you can get them (chives, thyme, sage, rosemary etc.)
 - 1 vegetable stock cube
 - squirt of tomato puree OR ketchup OR half a small tin chopped tomatoes
 - salt and pepper

Method

First  rinse and then cook the lentils until soft in enough water to cover, keeping an eye on them so they don't stick. This will take less time if you soak them beforehand.
Steam the potatoes; this can be done over the lentils if you have a colander and watch over it to make sure they don't boil over!
Chop, then fry the onion gently until fairly soft, then add other chopped vegetables and cook for a few minutes.
Heat up oven to gas mark 6.
Add the lentils, with cooking water, tomato puree etc, dried herbs (if using) and crumbled stock cube. Cook gently until vegetables are tender, adding more water if the mixture threatens to stick to the pan. Season to taste.Add fresh herbs now (if using).
Place lentil mixutre in a deep ovenproof dish; arrange potatoes on top, drizzle with oil and top with grated cheese. Alternatively, mash the potatoes before putting them on top, for a shepherd's pie effect.
Cook in oven until potatoes are golden brown.
Serve with a steamed green vegetable such as broccolli.