Peel potatoes and cut into quarters.
Peel the garlic cloves and break them apart.
Place potatoes and garlic cloves into a large pot and cover with cold water. Add 1 t. of salt to the water.
Over medium heat, bring to a boil and cook until tender, around 15 minutes.
Drain potatoes and rinse off the starch with warm water.
Move drained/dry potatoes to a large mixing bowl.
Run potatoes and garlic through a food mill (or ricer, or strainer). I use a hand mixer but I have to watch carefully to make sure I don’t beat the potatoes too long.
Add milk and butter gradually, mixing on low or by hand with a wooden spoon. Don’t overmix.
Season with salt and pepper, to taste.
Serve immediately or keep covered and warm.