1 pound potatoes, peeled and diced
1 pound parsnips, peeled and diced
1/4 cup light or heavy cream, heated
3 tablespoons unsalted butter, softened
1 1/2 teaspoons salt
black pepper to taste
scallions, chives, or fresh parsley, thinly sliced or chopped, for garnish (optional)
Place the potatoes and parsnips in a saucepan, cover with cold water, and bring to a boil. Reduce the heat, cover, and simmer until very tender, 20-30 minutes. Drain the vegetables and transfer to a large mixing bowl. Beat on medium speed until partially mashed, then continue to beat while gradually adding the cream, butter, salt, and pepper. Beat until smooth. Adjust the seasonings, transfer to a serving bowl, and garnish with the scallion, chive, or parsley. Serve immediately.
To make this in advance: After adjusting the seasonings place in a serving bowl, cover, and leave on the counter up to two hours. Reheat in the microwave for 2-3 minutes, stirring once half way through. Or, store in the refrigerator up to a day. Before reheating, pour a thin film of cream over the surface of the mixture. Heat for a minute in the microwave, stir, and continue heating until hot.