Prepare the potatoes by washing, peeling and cutting them into roughly 1″ cubes.
Place them in a large pot and cover with water. Add a teaspoon of salt to the water. Bring the potatoes to a boil over high heat, then reduce the heat to medium-high and allow them to simmer until tender, about 15-20 minutes.
Reserve a small amount of the water from cooking the potatoes. Drain the potatoes and set them aside.
Heat 1 tablespoon of butter in a skillet over medium heat. Add 2 cloves minced garlic and saute for 30 seconds, being careful not to burn it.
Add the potatoes, 1/2 cup half and half (or milk), 2 tablespoons sour cream (optional), salt and pepper.
Using a potato masher or fork, mash in your salt and pepper until you get the desired level of smoothness.
Continue mashing until it reaches your desired consistency. If the potatoes appear to be too thick, add a small amount of the reserved cooking water and continue mashing until smooth.
If you like, serve with additional butter and sour cream if desired. Garnish with chives (optional).