Wash the potatoes. Cook in boiling water for about 15 minutes. Heat oil in a pan. Fry in it for 7-10 minutes. Peel and chop the onions and add them to the mince after 5 minutes. Peel and dice the garlic.
Add tomatoes and garlic, simmer gently for about 10 minutes on medium heat, season with salt and pepper. Drain the potatoes and rinse with water. Wash and clean the savoy cabbage, cut the leaf ribs flat.
Blanch the leaves for 5 minutes in boiling salted water, quench cold. Melt fat, stir in flour, sweat for about 2 minutes while stirring. Add stock and milk, bring to the boil and simmer for about 1 minute.
Grate Gouda, melt 50 g in the sauce, season with salt, pepper and nutmeg. Peel the potatoes and cut into thin slices. Put one layer each of potatoes, savoy cabbage, cheese sauce and tomato minced ragout in a greased casserole dish.
Repeat the procedure. Wash and clean the tomato and cut into thin slices. Wash the parsley, dab dry, pluck the leaves from the stalks and spread on the casserole with the tomatoes. Sprinkle 150 g Gouda over the casserole.
Cook the casserole in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for approx. 45 minutes.