Lentil and Vegetable Stew

250g brown lentils
2 potatoes, peeled and diced
250g zucchini, sliced
1 large leek, trimmed and sliced
1 celery stalk
juice of 1 lemon
1 onion, finely chopped
oil
2 crushed garlic cloves
salt and pepper
2 Tbl parsley

Soak lentils overnight.
Bring lentils to the boil, then simmer until soft. Add potatoes, zucchini, leeks and celery. Cook until tender.
Fry onion and garlic in oil until soft and brown, add to the lentils together with parsley and lemon juice.
Simmer and add salt and pepper.