Peel the potatoes, remove any spots, lumps and cut them into quarters. Add to a large pot (6-quarand cover with cold water by one inch and add 1 teaspoon of salt.
Bring to a boil, reduce heat to medium-low and allow to simmer until fork-tender, for about 15-20 minutes.
Drain cooked potatoes by removing the water from the pot. Add in the hot milk, hot cream, butter, onion powder, and sour cream.
Mash the potatoes with a potato masher until smooth, adding a little extra milk or cream if needed. Careful NOT to overbeat, as they will become gluey.
In the end, stir in the garlic and season with salt and pepper to taste.
Serve hot, garnish with green onions and butter.
