The origins of Dosa have been widely discussed in literature and books. A few of them are listed below:
"The Story of our Food", a book written by K. T. Achaya, an eminent Indian food scientist and food historian, states that foods like Appam, Idiyappam, Dosa and Adai were already known in ancient Tamil country around 1st century AD, as per references in Tamil Sangam literature
Dosa, a common breakfast dish and street food, is rich in carbohydrates, and contains no sugar or saturated fats. As its constituent ingredients are rice and Urad Dal (Vigna mungo), it is gluten-free and becomes a complete protein. The fermentation process increases the vitamin B and vitamin C content. There are also instant mix products for making dosai, with somewhat lower nutritional benefits.
A mixture of rice and urad dal or ulundu that has been soaked in water is ground finely to form a batter. The proportion of rice to lentils is basically 4:1 or 5:1. The batter is allowed to sit overnight and ferment (adding a pinch of yeast helps). After the overnight fermentation, save some of the batter (in the refrigerator) as a starter culture for the next batch (since it is a sourdough culture, and acid, it should keep about a week). Sometimes a few fenugreek seeds are added to the rice-urad mixture. The rice can be uncooked or parboiled. The mixture of urad dal (black lentils) and rice can be replaced with highly refined wheat flour to make a maidadosai, or semolina for a rava dosai.
A thin layer of the batter is then ladled onto a hot tava (griddle) greased with oil or ghee (clarified butter). It is spread out evenly with the base of a ladle or bowl to form a pancake. A dosai is served hot, either folded in half or rolled like a wrap. It is also served usually with aloo curry, chutney, or sambar.
Cheese dosa served with sambar and fresh coconut chutney.
Dosa can be stuffed with fillings of vegetables and sauces to make a quick meal. They are typically served with a vegetarian side dish which varies according to regional and personal preferences. Common side items are:
Wheat batter mixed with fenugreek leaves, spread on a griddle.
Though dosa typically refers to the version made with rice and lentils, many other versions exist, often specific to an Indian region. Some variations include egg dosa, which is spread with an omelette, and cheese dosa, which is stuffed with cheese.
The Davanagere Benne Dosa (Kannada: ದಾವಣಗೆರೆ ಬೆಣ್ಣೆ ದೋಸೆ) or Butter Dosa is a dish originated in Karnataka. Butter is used instead of oil when frying, and a small amount is placed on top of it while serving.
Open dosa: chutney powder is spread on it while cooking, before serving, spiced and mashed potato is placed on top
Onion dosa: spread with chopped and sautéed onions
Ghee (thuppa/nei) dosa: ghee is used instead of oil while frying.
Roast: the dosai is spread thinly and fried until crisp.
Kerala dosa: a different kind of traditional dosa, it is small, thick, soft and spongy. It is more like a pancake and somewhat similar to appam, but dal is used in the batter for appam, and the appam is not flat.
Family roast: a long dosa which can be spread over two or three feet
Paper dosa: a long and very thin, delicate dosa which can be spread over two feet
Green dosa: stuffed with fresh vegetables and mint chutney
Thalir dosa:made of Maida and is very soft and delicate,eaten with sugar.
Chow-chow dosa: stuffed with (Indian flavored) Chinese noodles
Masala dose: stuffed with spiced potatoes, invented by Udupi hotels
Set dosa: a popular type of dosa in Karnataka, it is cooked only on one side and served in a set of two to three, hence the name.
Cabbage dosa: made of cabbage, a paste is prepared with rice, red chillies, asafoetida and turmeric. Once the batter is ready, cabbage cut into small pieces is added to the paste and left for about 30 minutes. Once this is done, the batter is poured and the dosa is made crisp
Neer dose (Kannada: ನೀರ್ ದೋಸೆ): It literally means Water dosa. It is a very famous delicacy from Karnataka. It is part of Udupi cuisine. Rice is soaked in water for 3 to 4 hours. It is then ground to make a runny rice batter. Most types of dosa require the batter to be fermented for a few hours or even a day. However, fermentation can be skipped while preparing a neer dose. Salt is added. A thin layer of batter is poured onto a heated flat griddle (tawa) greased with oil. The batter is spread with the base of a ladle or bowl to form a pancake. It is flipped to heat both crusts and removed from the griddle when the crust becomes dry. It is served hot.
70 MM dosa: similar to masala dose, it is larger, about 60 cm in diameter
American chop suey dosai: served with a filling of fried noodles and tomato ketchup
Uppu Huli Dose (Kannada: ಉಪ್ಪು ಹುಳಿ ದೋಸೆ): This is originated in Karnataka and is a very popular break fast dish in Mangalore and Udupi of Karnataka. It is made by adding Uppu (salt in Kannada) and Huli (the taste of tamarind in Kannada) to the batter. It requires no accompaniment of Chutney or Sambar.
Chinese masala dosa: noodles and other Chinese ingredients like schezwan sauce are added
Paneer chilli dosa: stuffed with sautéed cottage cheese (paneer) and capsicum
Keerai Masala dosa: coated with a thin layer of puréed spinach, and filled with the traditional potato/onion mixture
Egg Masala dosa: one or two fried eggs served on top
Davanagere benne masala dose (Kannada: ದಾವಣಗೆರೆ ಬೆಣ್ಣೆ ಮಸಾಲೆ ದೋಸೆ ): named after Davanagere in Karnataka, this is prepared by adding liberal doses of butter and also a potato filling.
Set Masala dose: or simply set masale contains two smaller masala dose. Sometimes one of them is filled with vegetable korma/kurma and the other one with the usual potato-onion mix.
In Bangalore, the masala dose is usually served with a red chutney applied to its inside surface. The red chutney usually has generous amounts of garlic.
Pesarattu: a dosai-like preparation prepared from mung bean, which is typically served with a ginger and tamarind chutney in Andhra Pradesh. The variations include:
using soaked whole moong seeds (along with green cover), which gives a greenish tint to the pesarattu; and
using yellow-coloured moong (green cover is removed and the dal is refined), which gives a golden-yellow tint to it when roasted.
Adai: a dosa-like dish prepared from a combination of lentils, namely urad, kadalai and moong paruppu.
Appam, aappam or hopper in Sri Lanka — a pancake prepared from a combination of patted rice (avalakki), rice and yoghurt. The primary differences between an appam and a dosai are that an appam is thicker (up to five times as thick as a dosa), can optionally contain curd, the dough differs in the ratio of rice and ulundu and is more finely ground than dosa batter, the center is thicker and the outer rim is very thin (whereas a dosai is more or less uniformly thick). Sometimes other ingredients are added to the top of the appam as it is cooked. This gives rise to the Sri Lankan "egg hopper" where an egg is cooked on top of the appam/hopper as it is fried, or the uttapam (see below).
Uttapam: a dosai-like dish made by cooking the ingredients in its batter. Unlike a dosai, which is crisp and crepe-like, an uttapam is a thick pancake. Uttapam is sometimes characterized as an Indian pizza.
^Raja M - The dosa, like most other south Indian culinary exports, is often linked to Udipi, a small temple town in the state of Karnataka. "India's new offering to curry Western flavor". Asia Times, June 24, 2004. Retrieved 2010-08-23.