Question: What legume is used to make Paddu?
Context: Canavalia gladiata, usually called sword bean, is a domesticated plant species in the legume (Fabaceae) family.  The legume is a used as a vegetable in interiors of central and south central India, though not commercially farmed.  In Telugu it is called "chamma kaya" also called "Tammi kaya".  In Tamil it is called "valavaraik-kay" or "valavaran-gai" which means, the vegetable that looks like a sword.  In Khmer, it is called "sânndaèk triës" (សណ្តែកទ្រៀស). The lentil ("Lens culinaris") is an edible pulse.  It is a bushy annual plant of the legume family, known for its lens-shaped seeds.  It is about 40 cm tall, and the seeds grow in pods, usually with two seeds in each. Detarium microcarpum (Bambara: "Ntamajalan" ), commonly known as sweet detar, sweet dattock or tallow tree, is an under-utilized tree legume that grows naturally in the drier regions of West and Central Africa.  It is a multipurpose species, with a wide range of uses due to its medicinal properties, edible fruit (eaten raw, cooked or made into flour with many uses of its own) and hardwood used as fuel-wood.  Its many uses make it a valuable and appreciated species to local communities but further research and efforts are needed for its domestication. Lupinus, commonly known as lupin or lupine (North America), is a genus of flowering plants in the legume family, Fabaceae.  The genus includes over 200 species, with centers of diversity in North and South America.  Smaller centers occur in North Africa and the Mediterranean.  Seeds of various species of lupins have been used as a food for over 3000 years around the Mediterranean and for as much as 6000 years in the Andean highland, but they have never been accorded the same status as soybeans or dry peas and other pulse crops.  The pearl lupin of the Andean highlands of South America, "Lupinus mutabilis", known locally as "tarwi" or "chocho", was extensively cultivated, but no conscious genetic improvement other than to select for larger and water-permeable seeds seems to have been made.  Users soaked the seed in running water to remove most of the bitter alkaloids and then cooked or toasted the seeds to make them edible, or else boiled and dried them to make "kirku".  Spanish domination led to a change in the eating habits of the indigenous peoples, and only recently has interest in using lupins as a food been renewed. Kuzhi paniyaram (Tamil:குழி பணியாரம்) or Paddu (Kannada:ಪಡ್ಡು) or Gunta Ponganalu (Telugu:గుంట పొంగణాలు) or is an Indian dish made by steaming batter using a mould.  The batter is made of black lentils and rice and is similar in composition to the batter used to make idli and dosa.  The dish can also be made sweet or spicy depending on the ingredients jaggery and chillies respectively.  Paniyaram is made on a special pan that comes with multiple small fissures.  It is known by various names in South India, including "paddu", "appe", "guliappa", "gulittu", "gundponglu", "ponganalu". The legume lectins (or L-type lectins) are a family of sugar-binding proteins or lectins found in the seeds and, in smaller amounts, in the roots, stems, leaves and bark of plants belonging to the Fabaceae family.  The exact function of the legume lectins "in vivo" is unknown but they are probably involved in the defense of plants against predators.  Related proteins in other plant families and in animals have also been found.  They have been used for decades as a model system for the study of protein-carbohydrate interactions, because they show an amazing variety of binding specificities and are easy to obtain and purify.  Over the years, a The peanut, also known as the groundnut and the goober and taxonomically classified as Arachis hypogaea, is a legume crop grown mainly for its edible seeds.  It is widely grown in the tropics and subtropics, being important to both small and large commercial producers.  It is classified as both a grain legume and, because of its high oil content, an oil crop.  World annual production of shelled peanuts was 42 million tonnes in 2014.  Atypically among crop plants, peanut pods develop underground rather than aboveground.  It is this characteristic that the botanist Linnaeus used to assign the specific name "hypogaea," which means "under the earth." Colophospermum mopane, commonly called mopane, mophane, mopani, balsam tree, butterfly tree, or turpentine tree, is a tree in the legume family (Fabaceae), that grows in hot, dry, low-lying areas, 200 to in elevation, in the far northern parts of southern Africa.  The tree only occurs in Africa and is the only species in genus "Colophospermum".  Its distinctive butterfly-shaped (bifoliate) leaf and thin seed pod make it easy to identify.  In terms of human use it is, together with camel thorn and leadwood, one of the three regionally important firewood trees. Haematoxylum brasiletto, or Mexican logwood, is a species of tropical hardwood tree in the legume family, Fabaceae.  It is known in its native Mexico and Guatemala as "palo de brasil" or "palo de tinto".  The timber is used to make bows for stringed instruments, the manufacture of dyes and in ethnobotany. Erythrina edulis (Basul) is a nitrogen fixing tree that is native to the Andean region from western Venezuela to southern Bolivia.  Nowadays it is known in Venezuela as “Frijol mompás”, in Bolivia, Peru and Argentina as “Pisonay”, “Pajuro”, “Sachaporoto del basul” or “Poroto del sacha”, in Colombia as “Chachafruto”, “Balú”, “Baluy” or “Sachaporoto” and in Ecuador as “Guato”.  Although it is widely known, it is not commonly cultivated.  Future research is needed, especially in agroforestry.  Basul is a legume and so it produces protein-rich beans covered in pods which can be used for human or animal nutrition.  The leaves and branches can be used as fodder.  Besides the agricultural aspects, "Erythrina edulis" can also be used as a fence plant.
Answer: lentil