Aligot Gratin

Directions

1. 1
   In a large saucepan combine potatoes with salted water to cover by 2 inches and simmer until very tender, about 50 minutes.
2. 2
   Drain potatoes.
3. 3
   Return potatoes to pan and heat over low heat, shaking pan, until dry.
4. 4
   Cool potatoes until they can be handled.
5. 5
   Peel potatoes and force through a ricer or medium disk of a food mill into pan.
6. 6
   Add butter, garlic, and milk and cook mixture over moderately low heat, beating constantly with a wooden spoon, until fluffy and heated through, about 2 minutes.
7. 7
   Add mozzarella and salt and pepper to taste and cook mixture, beating until cheese is melted and forms long elastic strands when lifted with spoon.
8. 8
   Divide aligot among 6 buttered 1-cup shallow gratin dishes or one 6-cup buttered gratin dish.
9. 9
   Aligot may be prepared up to this point 1 day ahead and chilled, covered.
10. 10
    Bring aligot to room temperature before proceeding with recipe.
11. 11
    Preheat broiler.
12. 12
    In a bowl with an electric mixer beat cream until it holds soft peaks and beat in horseradish and salt to taste.
13. 13
    Spread horseradish cream over aligot and broil about 4 inches from heat until golden, about 1 minute.