Peel and cut potatoes into 1" chunks. Place into a large pot, and cover with 1" of water. Salt and bring to a boil. Boil potatoes for 12-15 minutes or until fork tender.
Meanwhile, add remaining butter to a medium pan over medium heat. Add onion, garlic, and cabbage. Saute for 5-7 minutes or until cabbage is tender and onions are translucent.
Drain potatoes. Add ¼ cup of butter, heavy cream, salt and pepper. Mash until smooth and no lumps remain.
Add cabbage mixture to mashed potatoes. Add cooked crumbled bacon, and green onions. Fold to combine.
Serve with an additional pat of butter overtop.
