Preheat oven to 400°F.
Grease casserole dish (a larger shallow dish is better than a deep one - there's more crust to enjoy!)
Place separated potato slices in the dish in rows, as if you were shingling a roof, by overlapping rows. Once your dish is almost full, push the rows back so that they are almost vertical against the back of the dish. Now keep adding rows of potato slices, pushing back as the dish is filling. (Your rows will almost be vertical in the end.)
Sprinkle with salt and freshly ground pepper.
Pour heavy cream over the potatoes.
Bake, uncovered, for about 60 minutes. Sprinkle with cheese, if using, and continue baking for about another 30 minutes or until potatoes are tender and top is nicely browned.
