Peel the potatoes, chop them roughly and cook them in salted water. Then drain, steam and keep covered and warm.
Clean the shallots and garlic, cut into fine cubes and sauté in the butter until translucent. Clean the ginger root, grate it finely, add it to the pan and sweat it lightly. Stir in the nutmeg zest and cream and heat briefly.
Now chop the potatoes with a pounder, add the contents of the pan and stir everything until a homogeneous mash is formed.