Sour Cream Mashed Potatoes
- 3 pounds russet or mixed potatoes, peeled, cut into 2″ pieces
- 1 pound Yukon Gold potatoes, peeled, cut into 2″ pieces
- Kosher salt
- 1-cup heavy cream
- 1-cup whole milk
- 1/2 cup (1 stick) unsalted butter; plus more for serving (optional)
- Freshly ground black pepper
- 1/2-cup sour cream
Set oven rack in middle position and preheat the oven to 450 degrees F. Line a baking sheet with aluminum foil.
Place potatoes in a large pot and cover with cold water by 2″. Generously season with salt and bring to a boil. Reduce heat and simmer until tender, 10–15 minutes. Drain and transfer potatoes to a baking sheet; let stand until dry, 10–15 minutes. Set pot aside.
Meanwhile, heat cream, milk, and butter in a medium saucepan over medium heat; season with salt and pepper.
Pass potatoes through ricer into reserved pot. Mix in warm milk mixture, then sour cream; season with salt. Serve topped with pepper and more butter, if desired.