1. Peel and cut the vegetables into pieces.
Steam them using a steamer, for about 30 to 40 minutes.
2. Check the doneness of the vegetables using a knife.
3. Meanwhile, melt the butter in a pan.
Peel and cut the onion in half, then finely slice it widthwise.
Sweat the onions in the butter.
4. Add the ground meat and mix.
Season with salt, pepper, and add the parsley.
5. Towards the end of cooking, deglaze the meat with white wine.
6. Once the vegetables are cooked, mash them and incorporate the cream and nutmeg.
7. In an oven-safe dish, place the meat and cover it with the mashed vegetables.
8. Grate some Parmesan cheese or sprinkle pre-grated Parmesan on top of the mashed vegetables.
9. Preheat your oven to 180°C and bake the dish.
10. Bake for 20 to 30 minutes, until the surface is gratinated.