Peel kohlrabi and cook in boiling salted water for about 45 minutes. Cook rice in 250 ml salted water for about 10 minutes. Clean, wash and quarter the tomato. Remove seeds and cut the flesh into cubes. Remove kohlrabi from the cooking water with a skimmer and rinse with cold water.
Let it cool down a little. Cut off one lid each and hollow out with a sharp knife. Cut the flesh into small pieces. Mix rice, tomato cubes, peas, kohlrabi leftovers and crème fraiche. Season with salt and pepper. Pour the mixture into the kohlrabi. Grate the cheese and sprinkle it over the kohlrabi. Cover as desired with the kohlrabi lid and place in a flat casserole dish. Mix 1/4 litre of kohlrabi cooking water and tomato paste and pour into the kohlrabi.
Pour the mixture into the kohlrabi. Grate the cheese and sprinkle it over the kohlrabi. Cover as desired with the kohlrabi lid and place in a flat casserole dish. Mix 1/4 litre of kohlrabi cooking water and tomato paste and pour into the kohlrabi. Bake in the preheated oven (electric: 200 °C/ gas: level 3) for about 25 minutes. Sprinkle with chervil leaves