[8] Less than a month later an Associated Press story credited a Los Angeles chef named Ken Seusa at the Kin Jo sushi restaurant near Hollywood as its inventor.

[5][12] According to this account, Mashita began substituting the toro (fatty tuna) with avocado in the off-season, and after further experimentation, developed the prototype, back in the 1960s[13][14][15] (or early 1970s[16]).

[17] One story, drawn directly from a firsthand source (namely Teruo Imaizumi, Mashita's assistant), was that in 1964, the pair developed a prototype which used cubed avocado, king crab, cucumber and ginger, made into a hand-roll (rather than makizushi rolled using a makisu).

[5] The early California roll was wrapped traditional style, with the nori seaweed on the outside, which American customers tended to peel off.

[16][b] Japanese-born chef Hidekazu Tojo, a resident of Vancouver since 1971, claimed he created the California roll at his restaurant in the late 1970s.

According to Tojo, he single-handedly created the California roll at his Vancouver restaurant, including all the modern ingredients of cucumber, cooked crab, and avocado.