Wash the potatoes and cook covered for about 20 minutes. Quench, peel and let cool.
Clean and wash the cauliflower and divide it into florets. Cook in approx. 1⁄2 l boiling salted water for 8-10 minutes. Drain and collect the vegetable water.
Peel and finely dice the onion and garlic. Wash the meat, dab dry and cut into small cubes. Wash and chop the marjoram, except for something to garnish.
Fry the meat in hot oil while turning it. Fry the onion and garlic briefly. Season with salt and pepper. Brown the tomato paste. Add 1⁄8 l vegetable water, tomatoes with juice, broth and marjoram.
Mash the tomatoes a little. Bring to the boil and simmer for about 10 minutes. Season turkey bolognese with salt, pepper and paprika to taste.
Cut the potatoes into slices and fill them into a greased casserole dish. Put cauliflower florets on the edge and turkey bolognese in the middle. Grate the cheese and sprinkle over it. In a preheated oven (electric cooker: 200 °C/circulating air: 175 °C/gas: level 3) approx.
Bake for 20 minutes. Garnish with marjoram.