Peel and wash the potatoes, cover and cook in salted water for about 20 minutes. Preheat oven (electric cooker: 225 °C/circulating air: 200 °C/gas: see manufacturer). Line a baking tray with baking paper.
Wash rosemary, dab dry, pluck needles and chop coarsely. Mix with oil, salt and pepper. Wash fish, dab dry and cut into 4 pieces (approx. 3 cm wide). Brush with rosemary oil and wrap each piece with 1 slice of ham.
Place on a baking tray and bake in a hot oven for 12-15 minutes.
In the meantime, clean and wash the broccoli and cut it into florets. Peel and chop the stems. Cover them and stew in a little salted water for about 5 minutes. Drain the broccoli and season with pepper.
Drain the potatoes. Add milk and mash to puree. Season to taste with salt and nutmeg. Arrange everything.