Peel the onion, halve and quarter. Clean carrots and parsley root and cut into pieces. Also clean the leek, cut into rings. Celery in pieces. All together in one powerful machine or something similar that you have. Add sea salt and puree everything together.

Put some of it in a glass and put it in the refrigerator for later use. The other is placed on a baking sheet that is lined with paper. Set the oven to 100 degrees and preheat. Then slide in the baking sheet and leave to dry for about 1 hour with the door slightly open.

Then switch off the oven and let it cool down overnight. The next day, put in a powerful machine that can pulverize wherever. Also put the vegetable powder in a jar, which you can close.