Scalloped Potatoes (Patates au Gratin)
Gratineed potatoes are a very common side dish in Greece, as they are here. Nobody really thinks of them as “French,” even if they use the French word “Gratin.” But of course they are French, and I use the recipe given by Julia Child in “Julia and Jacques: Cooking at Home.”
This is really a very simple dish of sliced potatoes cooked in milk, with a bit of salt, pepper, and garlic for flavor. The starch from the potatoes thickens the milk to make a rich, creamy sauce. It is cooked first on the stove top to heat the milk and begin the thickening process, then finished in the oven, where the potatoes become tender and the surface browns.
Scalloped potatoes are an easy dish for entertaining, because you can make them a few hours or even a day ahead of time. They taste great either reheated or served at room temperature.
Cookware considerations: Because this dish needs to cook on both the stove top and in the oven, a shallow flame-proof dish is ideal. I have a nifty ceramic pot that my sister brought me from China that can go from the stove top to the oven and is also attractive for serving. I’ve also used my 5 quart dutch oven – it’s deeper than necessary, but works fine. Before I had these, I used to start the milk-and-potatoes in a large pot on the stove, and then dump them into an 8 X 8 pyrex baking dish. This method works great too, it’s just that you have one more pot to wash. Whichever method you use, if your baking dish is so shallow that the liquid might bubble over, put a cookie sheet underneath it to save yourself a mess in the oven.
Here is Julia Child’s recipe, very slightly adapted by me:
1 tsp salt
1 clove garlic, minced, pressed or grated on rasp grater
3 cups milk, or milk mixed with cream according to your heart’s desire
1/2 tsp white pepper
2 lb yukon gold potatoes, or other boiling potatoes such as white or red potatoes (preferably not Idaho russet potatoes as they’ll tend to fall apart)
optional: a handful of grated cheese
1. Peel the potatoes and put them in a bowl of water.
2. In a pot large enough to hold the milk and the potatoes, put the milk, salt, pepper, and garlic.
3. Slice the potatoes very thinly – 1/8 inch or less. Use your food processor if you have one!!! Put the sliced potatoes into the milk right away.
THIS IS THE KEY TO THIS RECIPE: ONCE THE POTATOES ARE SLICED, NEITHER RINSE THEM NOR PUT THEM IN WATER! THEY GO DIRECTLY INTO THE MILK MIXTURE IN THE POT!!!
Okay, I’ll quit shouting. Scalloped potatoes do not need flour because the potato starch thickens the dish. The reason the potatoes need to be sliced so thinly is to expose as much starch as possible, and you do not want to wash that starch off.
4. Preheat oven to 400 degrees.
5. Bring the milk and potatoes to a slow boil over medium high heat on your stovetop and cook for a few minutes to start the sauce thickening. Stir and scrape the bottom of the pot occasionally to prevent sticking or burning. A thick-bottomed pot will help here. If your pot has a thin bottom, use lower heat and stir/scrape a lot.
6. If you’ve used stove-top-to-oven cookware, just put it in the oven now. If not, dump the food from your pot into your baking dish, push down any slices that are sticking out of the milk, and put it in the oven. But read #7 before you actually put it in, because you have a decision to make.
7. For the Greek version of this dish, top with a handful of grated kefalotiri, which is similar to Parmesan. Or you could top with any grated cheese you like. You don’t really need to use a cheese topping, because the gratin will brown nicely without it, especially if you’ve used some cream in with the milk. When I make extra-creamy versions for company, I never add cheese. On the other hand, if you’ve used low-fat or skim milk, and no cream, you might need some cheese on top to enhance browning, or you can dot the top with butter for the same purpose.
8. Bake for 40 to 50 minutes. The top should be nice and brown, and the potatoes should be tender. I take them out after 40 minutes and they’re always fine, so don’t sweat it. Oh yes, ideally the potatoes will have “drunk” (i.e., absorbed) most of the liquid, but again, don’t worry, any liquid remaining will be thick, creamy and delicious.