Creamy Mascarpone-Mashed Potatoes
Mashed potatoes can be made up to 2 days in advance. Reserve and refrigerate 1 cup cooking water. Let mashed potatoes cool to room temperature, about 30 minutes. Refrigerate in an airtight container. Reheat in a pot over medium-low, stirring often and gradually stirring in some reserved cooking water, until creamy and warmed through, about 10 minutes.