Fry the minced meat in a little oil in a large saucepan, season with salt and pepper. In the meantime, peel and dice the kohlrabi and potatoes, coarsely chop the kohlrabi leaves, add everything to the chopped. Add 2 to 3 liters of water and 2 teaspoons of granulated broth, then simmer for about 20 minutes over medium heat.
When the kohlrabi and potatoes are done, season the stew with salt and pepper and thicken with mashed potato powder as desired.