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Sweet Potato, Gouda and Herb Gratin
http://expatriateskitchen.blogspot.com/2006/11/taute-cuisine-6-battle-orange.html

Recipe is a ways down in the post. Amazing.

lgvw1963 put so much thought into that answer ... I feel kind of guilty about just looking at my old Betty Crocker cookbook, in which scalloped potatoes are made without cheese and au gratin potatoes are made with cheese. Basically the same otherwise.

Gratin dauphinois doesn't have cheese, unless you add a little to the top to brown at the end of cooking. At least, none of the recipes I've seen require cheese. But lots of people add it anyway.

I don't think there is a technical difference between the 2, other than usage and language.

A gratin is a general category quite similar to a casserole: mix something with a creamy sauce and bake in a wide shallow dish until it's crusty on top.

I've had things called scalloped potatoes that werent baked, so maybe that's a difference (though I've had "scalloped potatoes" that were baked).

I've posted mine elsewhere on this site, but I'll put it here because it's so easy. It's basically from Cooks Illustrated/The Best Recipe, and is as reliable as you'd expect.

Basically you slice potatoes thinly (I prefer yukon golds, but russets are also fine), about 1 per person. Put into a large pot with enough half and half to come up the top of the potatoes. Season generously with salt, pepper, nutmeg if you like. Bring to the boil, cut the heat, and then pour it all into a buttered baking dish. (You can rub the dish with a cut clove of garlic if you like, after you butter and before you add the potatoes.) Then bake, covered, at 400F for about 35-45 minutes, until tender (depends in how long it took to boil, how thin your slices were). Remove foil, add cheese if desired, and bake until browned and bubbly, about 15 minutes more.

Changes are easy: stir in any herbs or whatever interests you, grated cheese if you like, bacon or ham if you want. My MIL adds saffron, which is great but may not go with what you're serving, and omit the nutmeg.

If you want it to look fancy, I'd still pour most of the potatoes into the dish and just keep back a few to arrange artfully on the top (in rows or concentric circles or whatever). I first learned to make the dish by layering the slices one by one. Took forever, was a pain in the hiney, and so totally unnecessary. If you mix in your cheese in the pot with the potatoes and half and half, it will get evenly distributed and you won't know the difference, unless you actually want it to be layered like a lasagne.

Actually, Renzata, Gratin Dauphinois is a traditional dish from the French Alps and they love their gruyere, so cheese is included in the dish but I do agree with you about the yukon golds. They would be yummy in the dish; so would yellow finn & you probably wouldn't need to peel them cuz they're so thin skinned. Yaay! One less step.

Here's a French culinary site that shows the cheese in the dish & discusses the origin of the dish. They like it between the layers as well as on top.
http://www.cuisine-france.com/recette/gratin-dauphinois.htm

Technically, there is no difference between "au gratin" or "scalloped potatoes". It's just semantics, depends on where you hail from. Different people call the same dish different things. We probably have those god-awful Betty Crocker freeze-dried mixes to blame for the confusion. They were likely trying to sell the same mix under two different names to double their market-share.

BTW, I would never cite Gourmet magazine or it's cookbooks as a reference. While lovely to look at, it's not always reliable.

I revere Thomas Keller and his restaurants which I've been lucky enough to eat in; but, we all know he does his own wonderful take on "classic" dishes.

The C.I.A. Manual includes cheese in the crust but not in the layers.

The Joy of Cooking while an American institution is hardly an authority on French Cuisine. Sorry, America, my mom had a much dog-eared copy of it, too

Anthony Bourdain is a great writer (his Confessions from the Kitchen started this whole chef as celebrity, top chef, restaurant wars revolution & his No Reservations show is great, loved the episode with Eric Ripert). He was probably a good chef at Les Halles, but I've never seen a cookbook written by him.

Julia Child, an American cooking icon who was never a chef but was a huge francophile who lived & studied at Le Cordon Bleu in France, used gruyere in her gratin dauphinois.

I agree that custardy is more desirable than cheesy except in the crust which should be crisp not creamy or else it's not a gratin (gratin signifies the upper crust in Paris); but, some cheese, not too much cheese, just the right amount is essential in the classic.

But, frankly, our difference of opinion isn't really important to the poster of the question. What is important is that she make a yummy dish that she and her family or friends can enjoy no matter what they call it. Agreed?

@All - You guys have given me some real "food" for thought here! I love both scalloped and au gratin.

@SSMom - ;-D !!!