Wash and peel the potatoes and cut into 1" chunks. Put them in a colander and rinse under cold water.

Get out a steaming basket and a pot that's large enough for the steaming basket. Add an inch of water to the pot, and put in the steaming basket. Bring the water to a boil and add the potatoes to the steaming basket. Cover the pot with a lid.

Turn the heat down to medium and steam for about 20-30 minutes or until tender. They should be fully cooked.

Meanwhile, in a small saucepan over low heat, add the milk, cream, garlic, and salt (I recommend using 1 1/2 teaspoons and adding more later, if desired). Once it's all melted, turn the heat off (but keep the saucepan on the stove so it stays warm).

Once the potatoes are fully cooked, remove the steamer basket from the pot and drain the water from the pot. Put the potatoes back into the pot and put the pot back on the burner (which is now off - if you have a gas or induction burner that's not still hot, then turn the heat to the lowest setting). Let any remaining moisture cook off for 1-3 minutes, shaking the pot occasionally.

With an electric hand mixer (turned off) or a potato masher, break up the large potato pieces first. Stir in the butter (with a large spoon or silicone spatula) so that it coats the potatoes. It doesn't have to be perfectly mixed in - it just has to be melted and coat the potatoes.

Add the milk mixture in 3 additions (using an electric hand mixer), starting off on low so that the liquid doesn't fly everywhere and then turning it up to high and beat until smooth and creamy. You need the full amount of liquid. Do not overmix! Taste and add more salt, if needed.