Preheat oven to 350°F. Roast sweet potatoes on a rimmed baking sheet until tender, about 1 hour. Let cool slightly.
Remove skins and transfer sweet potatoes to a large heavy saucepan over low heat. Add cream cheese and butter. Mash until well blended and creamy. Season with salt and pepper. Stir over low heat until hot.
Spoon into a warm serving dish and garnish with cheese and pecans.