According to wiki, gratin is a widespread culinary technique in which an ingredient is topped with a brown crust, often using breadcrumbs, cheese, eggs or butter. Gratin originated in French cuisine and is usually prepared in a shallow oven proof container. The word 'gratin' comes from French word 'gratter', meaning to scrape or to grate, referring to the scrapings of bread and cheese and the verb 'gratiné' meaning the crust. Potatoes gratine is the most common of gratins but the technique is used in cooking other vegetables, fish, meat and pasta dishes as well.
For the potato version, slices of boiled potato are put in a buttered oven proof dish, sprinkled with cheese and is baked / broiled until the top browns.I had about four potato dishes in mind for this marathon but eventually had to settle with two. The first one is this simple au gratin recipe that is not loaded with cream and cheese and can be a great side dish for those who do not prefer spicy dishes. I picked this recipe also for the reason that potatoes were not cooked on stove top. (I was sticking to 'only sauce making on stove top' rule of this marathon as I didn't know the rules were flexed at the time of preparing this.) The cream is replaced with fat free milk here thus making it a low calorie version. I used a 2 quart dish and followed the recipe in the same ratio but in a smaller quantity than given below. I didn't try to change anything other than keeping it a little spicier than the original version.
Recipe Source: Taste of home
3 tbsp. all purpose flour
Salt to taste
1/2 tsp ground pepper (I used more to suit our palates.)
2 cups 2% milk (I used mostly fat-free milk.)
1 cup Cheddar Cheese
5 cups peeled and thinly sliced potatoes (About 5 medium sized potatoes.)
1 big onion chopped
* Grease a 2 quart baking dish and keep it aside.
* After all the prep work is done, preheat the oven at 350 deg F.
* Melt butter in a sauce pan on low flame and add flour and pepper. Keep stirring until smooth.
* Add milk slowly and keep stirring to avoid the lumps. Bring the milk to a boil. (If you notice lumps in case, turn off the stove and pass the mixture through a stainer and smooth the lumps. And again start to cook.)
* Cook the mixture for about 2 minutes, until it thickens. Then add the cheese and turn off the stove. Stir until it melts, taste and then add salt accordingly. Add potatoes and onion to the mixture.
* Transfer the mixture to the greased baking dish. Cover the dish with an aluminum foil and bake for about one hour. Then uncover and bake again for about 30 to 40 minutes or until the potatoes are tender.