Sweet Potato Casserole

1 lb yams or sweet potatoes
3 T brown sugar, packed
1 T water
¼ t salt
½ pkg mini-marshmallows

Preheat oven to 350 degrees. Cook yams thoroughly either by baking or boiling. Mash yams, while still warm to remove lumps, and mix in remaining ingredients except marshmallows. Place in a lightly greased casserole dish. (At this point you can cover and refrigerate it to cook tomorrow.) Bake for 30 minutes or until heated through. Cover with a single layer of marshmallows and bake close to element for another 5 minutes or until marshmallows are lightly toasted. (If prepared yesterday, make sure to allow it to sit out for at least an hour before baking. If you put a cold baking dish directly into a hot oven, the dish will break.)