Using a potato variety that's high in starch, like Yukon gold, will give you fluffier mashed potatoes.
Place potatoes in a medium pot; cover with water, and season with salt. Bring to a boil; reduce heat, and simmer until tender, about 20 minutes. Drain, and let cool slightly. Peel potatoes, and pass through a ricer. Return potatoes to pot.
Add cream and butter, and cook over medium heat until warmed through. Season with salt and pepper, and stir to combine. Serve warm.
Potatoes can be refrigerated for up to 3 days. Reheat over low heat with a splash of cream.