For the vegetables, wash the potatoes, bring to the boil in water and cook for 20-25 minutes.
In the meantime, clean, peel and wash the carrots and cut into slices lengthways if necessary. Remove the leaves from the broccoli, wash the broccoli and cut into small florets.
Bring the broth to a boil. First add the carrots and cook for 3-4 minutes. Then add broccoli and cook for another 5 minutes. Drain the vegetables, catching the cooking liquid and, if necessary, top up with water to 250 ml (1/4 l).
For the minced meat mixture, peel and dice the onion. Heat oil in a pan. Sauté the onion cubes in it. Add the minced meat and fry, crushing the meat lumps with a fork. Season with salt, pepper and paprika and stir in the tomato ketchup.
Drain the cooked potatoes, steam them, peel them, cut into slices and layer them in a greased casserole dish like flakes. Sprinkle the potato slices with salt.
Melt the butter for the sauce. Heat the flour in it, stirring, until it is light yellow. Pour in the vegetable liquid and cream and whisk through with a whisk, being careful not to get any lumps. Bring the sauce to the boil while stirring, season with salt, pepper and nutmeg and stir in the cheese.
Spread the minced meat mixture on the potatoes, place the vegetables on top and cover everything with the sauce. Slide the form onto the rack in the oven.