For an even richer flavor, use whole milk or heavy cream instead of half-and-half. Roasting the garlic brings out its natural sweetness and mellows its sharp flavor. Don't skip this step! Yukon Gold potatoes are recommended for their creamy texture and naturally buttery flavor, but Russet potatoes can also be used. Adjust the amount of half-and-half to achieve your desired consistency. For extra fluffy potatoes, whip in a bit more liquid. Mashed potatoes can be made ahead of time and reheated. Store in an airtight container in the refrigerator for up to 3 days. Reheat gently over low heat on the stovetop, adding a splash of milk or cream to restore moisture.