Peel and chop the Yukon Gold potatoes, then place them in a pot of cold salted water and bring to a boil. Cook until tender, about 15-20 minutes.

While the potatoes are boiling, in a separate pan, melt the butter over medium heat and add the chopped scallions and shredded cabbage. Cook until the cabbage is tender, about 5 minutes.

Drain the potatoes and return them to the pot. Add in the milk, cooked cabbage and scallions, salt, black pepper, and nutmeg. Mash until smooth and creamy.

Taste and adjust seasoning as necessary before serving.