Clean, wash and coarsely chop the soup greens, except for half of the leek. Peel and halve the onion. Clean the mushrooms. Wash, clean and slice the tomatoes. Sauté onion in 1 tablespoon of oil.
Add soup vegetables, mushrooms and tomatoes, fry briefly. Season with salt and pepper. Add 1 litre of water and bring to the boil. Let simmer for about 45 minutes. Peel carrots and cut them into thin sticks. Peel kohlrabi and dice finely. Wash the rest of the leek and cut into rings. Sieve broth and bring to the boil. Cook vegetables in the stock for 5-10 minutes. Dice toast and roast in remaining oil.
Peel kohlrabi and dice finely. Wash the rest of the leek and cut into rings. Sieve broth and bring to the boil. Cook vegetables in the stock for 5-10 minutes. Dice toast and roast in remaining oil. Season stock to taste, serve. Add toast