Boil potato pieces until fork tender. Strain and remove from pan. Place pan over medium-low heat and melt butter in the pan. Add cream, garlic and green onion whites. Increase heat to medium and bring to a simmer. Simmer for 2 minutes, then reduce heat to low. Add potatoes, salt, pepper, cheese and onion greens. Stir with a spoon to mix all ingredients. Do not mash.
As with all recipes, check your potatoes for salt. You should be able to taste the salt without it being overwhelming. Potatoes require a lot of salt, and the salt will bring out the rest of the flavors of the dish.
