Place potatoes in a large Dutch oven and cover with 1-inch cold water.
Bring to a boil over high heat. Add a large pinch of salt.
Reduce heat to medium-low and simmer until potatoes are tender. Test by inserting a paring knife into the potatoes. There should be very little resistance. Should take about 20 minutes.
Drain the potatoes in a colander. Return the potatoes to the Dutch oven and allow to dry for a few minutes.
Over a large bowl, spoon a small amount of potatoes into the hopper of a ricer. Press them through the ricer. Add potatoes back into Dutch oven. Repeat until all the potatoes have been riced.
Stir unsalted butter into potatoes, tablespoon by tablespoon, with a wooden spoon, until smooth.
Gently stir in warmed half-and-half until fully incorporated.
Add salt and pepper to taste.