Peel the kohlrabi. Steam in hot salted water for 45-50 minutes. Take out, let cool.
Wash the zucchini and cut into bite-sized pieces. Peel the onion, dice finely.
Blanch the peas. Saute onion and zucchini in hot fat for 2 minutes. Wash, dry and finely chop the chives. Add to vegetables, season and let cool slightly.
Mix crème fraîche and egg until smooth. Coarsely grate cheese. Add two thirds of it to the prepared vegetables. Season with pepper and salt.
Cut a lid off each of the kohlrabi. Hollow out kohlrabi with a scoop or a teaspoon, leaving a rim about 1 cm wide. Finely chop the kohlrabi flesh and add to the prepared filling.
Now fill kohlrabi and place in the mold. Sprinkle with remaining cheese. Put the lid on each and pour vegetable soup.
Steam kohlrabi with peas in preheated oven at 200 °C for about 30 minutes.