May 27, 2009
Simple Sides: Potato Gratin
by Gareth Mark
Simple yet elegant, and always a hit, gratin is a dish that every cook should know how to make. There's nothing difficult about making a gratin, and once you understand how to make one, you'll be able to make a gratin any time you want using whatever you have at hand.
A gratin is sliced food layered with optional cheese and seasonings, topped with cream and optional bread crumbs, then baked at 350°F/175°C until done. The only thing special you'll need is a good porcelain gratin in which to make it.
For this gratin simply wash and peel some russet potatoes, then slice them into a bowl of slightly acidified cold water; I used the juice from a quarter of a lemon. The particular thickness of the potato slices isn't important so long as all the slices are the same; thicker slices takes longer to cook. Let the potatoes rest in the water for a few minutes to get the surface starch off.
To assemble the gratin, begin by brushing some clarified butter or olive oil into the baking dish. Pat the potato slices dry with paper towels, then lay them into the dish, add shredded or grated cheese, add a few cloves of garlic confit if you wish, then season with salt. I shaved some parmigiano reggiano for the cheese, and used Casina Rossa Truffle and Salt for the salt; truffle and potato is a classic combination. You can see the bits of truffle below.
To finish the dish, add another layer of ingredients, leaving out the garlic confit if you're using it, and a third layer if you're using a deep dish. Finish by adding cream to fill the baking dish about two-thirds full or so, being certain to wet the entire surface with the cream. Place in a 350°F/175°C oven and bake until done. It's going to boil over during cooking, so putting the gratin dish on a baking sheet to catch the spillage will save some oven cleaning.
You could easily substitute or add other vegetables, or fruits for that matter, change the cheese or leave it out, even add some sugar for a sweet gratin. Just layer whatever you slice with seasonings, finish with cream, and bake until done. In the unlikely event you have some left over, just reheat it in the microwave, or if you used vegetables, consider a frittata.