Mustard Mashed Potatoes

Directions

1. 1
   In a 5-quart kettle cover potatoes with cold salted water by 2 inches and simmer until tender, 35 to 45 minutes.
2. 2
   While potatoes are simmering, in a small saucepan heat milk with butter over moderate heat until butter is melted.
3. 3
   Remove pan from heat and keep milk mixture warm, covered.
4. 4
   In a colander drain potatoes and cool just until they can be handled.
5. 5
   Peel potatoes, transferring to a large bowl.
6. 6
   Add mustard, salt and pepper to taste, and three fourths hot milk mixture and with a potato masher mash potatoes until smooth, adding more milk mixture if necessary to make them creamy.
7. 7
   (Potatoes may be made 1 day ahead and cooled completely before being chilled in a buttered ovenproof dish, covered.
8. 8
   Bring potatoes to room temperature before reheating, covered.)