Heat the stock in a pan, stir in the bulgur wheat and leave to stand for 30 minutes. Then fluff up with a fork and let cool.
Peel and halve the onion and cut into thin strips.
Wash the parsley and coriander, shake dry and roughly chop the leaves. Mix the diced tomatoes, onion and herbs with the lemon juice, olive oil, salt and pepper and then combine with the bulgur wheat.
Season to taste and leave to stand for 20 minutes. Season again with salt and pepper before serving.