Place the lentils in a large bowl.
Cover with plenty of cold water, cover and leave to soak overnight.
The soaking water will become cloudy and the lentils will swell up. Remove any floating lentils from the surface of the water.
Tip the lentils into a sieve and allow to drain.
Peel and finely dice the onion.
Heat the oil in a large pan and saute the onion until golden.
Peel and dice the carrot and celery.
Add to the onions and saute for a few minutes. Mix the caraway and coriander and scatter over the vegetables.
Sprinkle with some lemon juice and pour in the stock.
Add the drained lentils to the pan, cover and simmer for 45 minutes over a medium heat.
Peel and finely chop the garlic.
Add to the pan.
Wash and dice the courgettes.
Add to the lentils for the last 10 minutes cooking time.
Add a little extra water If needed.
Wash the spring onions and cut them into fine rings.
Add to the pan and season with salt, pepper and lemon juice. Garnish with a lemon wedge.