Boniato Gratin

Directions

1. 1
   Boil the boniato in salted water to cover (at least 2 quarts) until very tender, 6 to 8 minutes.
2. 2
   Drain the boniato and return to the pan.
3. 3
   Mash the boniato to a coarse puree with a potato masher or fork.
4. 4
   Work in the cream, stock, coffee liqueur, salt pepper, and nutmeg.
5. 5
   The mixture should be highly seasoned and moist.
6. 6
   If necessary, add a little more stock.
7. 7
   Spoon the boniato mixture into a lightly buttered 8-inch gratin dish.
8. 8
   Sprinkle with the bread crumbs and dot with the butter.
9. 9
   (The recipe can be prepared several hours ahead to this stage.)
10. 10
    Preheat the oven to 400F.
11. 11
    Just before serving, bake the gratin until crusty and golden brown, 15 to 20 minutes.