Separate kale leaves of the top, cut the central part of the root with leaves and stew them into boiling water for about ten minutes. Rinse leaves in cold water and cut into strips. On the water, cook finely chopped leeks, celery and zucchini cut into bigger pieces. Add kale and pepper, pour water, add salt to taste and add a potassium salt and herbal spices and cook for 50- 60 minutes. When cooked add 1 tablespoon of olive oil.