Cook the potatoes with their skin on for about 20 minutes, meanwhile wash the chard and cut into pieces. Peel the potatoes and cut into pieces about one centimeter thick.
Slowly melt the butter in a pan, sauté the onions and half of the chopped garlic, add the chard and after another 10 minutes add the potato cubes.
Grind the coriander seeds and peppercorns, add to the vegetables and season with salt and nutmeg.
Fish:
In a pan suitable for the oven, fry some butter, the other half of the garlic and the fish on both sides.
Add tomatoes, fry briefly, season with salt and pepper to taste.
Cover with parmesan and grill in the oven at 200 degrees top heat or grill function.