Cut the white cabbage (without the stalk) into wide strips. Sauté in 1 tablespoon oil in a pan for about 5 minutes while turning. Pour in the vegetable stock and cover and let simmer for about 10 minutes. Sieve, collect the broth.
Cut the chicken fillet into strips, season a little with paprika, pepper and salt, fry on all sides in 1 tablespoon oil until crispy. Add the onion and sauté with it. Remove meat, keep warm.
Cut the potatoes into thin slices. Fry in 1 tablespoon oil until crispy, turning occasionally, add a little salt if necessary. Pour in the broth and stir in the sour cream. Mix the milk with the flour and add to the pan. Stir and bring to the boil. Now season everything well. If the sauce is a little too stiff, add a little more milk.
Add the meat and cabbage, stir together and let warm.