Peel and cut the carrots, potatoes, and butternut squash. Steam for 30 to 40 minutes, or cook in a pressure cooker for 10 to 12 minutes.

Check if the vegetables are cooked by piercing them with a knife.

Melt the butter in a skillet and sauté the sliced onions until soft.

Add the meat to the onions, season lightly with salt and pepper, and add the parsley. Cook together for 15 to 20 minutes.

At the end of cooking, deglaze the meat with the white wine.

Mash the cooked vegetables, then mix in the sour cream and nutmeg.

Preheat the oven to 350°F (180°C).

In an oven-safe dish, spread the meat mixture, then cover with the vegetable mash.

Top with shaved or grated Parmesan cheese.

Bake for 20 to 30 minutes, until the top is golden and bubbly.