Put cabbage in boiling salted water. Remove the 8 outer leaves at intervals of 2-3 minutes. (Use the rest of the cabbage for other purposes.) Cut the leaves in half lengthwise. Wash apples, quarter them and remove seeds.
Cut quarters into small pieces. Peel and finely chop the onions. Mix 2 onions, apples and ham. Season with thyme and pepper. Spread the apple mixture on the cabbage leaves, roll them up and pin them with wooden skewers.
Wash, peel and cut the potatoes into pieces. Heat oil in a coated pan. Fry the cabbage rolls in it while turning, remove. Fry the minced meat and potatoes in the frying fat for about 5 minutes.
Add the remaining onion cubes. Season with salt and pepper. Chop the tomatoes in the tin a little bit and add. Pour in vegetable stock. Bring to the boil, place cabbage rolls on top and cook over medium heat for about 15 minutes.
Arrange on plates and garnish with thyme.