Tenpura is the oldest topping for soba said to have originated when tenpura such as scallop kakiage (a type of tenpura made by deep-fat frying the mixture of scallops, chopped vegetables, and the tenpura batter) was used during the mid Edo period.
種物としては最も古くからあり、江戸中期に貝柱のかき揚げなどを載せたのがはじまりという。