First peel the potatoes and cut them into quarters. Bring water to a boil and cook the potatoes for 10 minutes.
Then toss in a pan with the melted butter and the rosemary sprig, season with salt and garnish with finely chopped parsley.
In another pan, fry calamari for a few minutes with the grated garlic in the oil.
Serve the calamari with the potatoes.