The sushi burrito keeps the silhouette of a Mission-style burrito and replaces nearly everything inside it. The wrapper is not flour but a full sheet of nori; the binder is not rice and beans but seasoned sushi rice; the core is not griddled meat but the contents of a maki roll scaled up to handheld size. It is a fusion object, explicitly Californian in logic, that borrows the burrito's geometry, a tight cylinder eaten in the hand without slicing, and pours a Japanese vocabulary into it. The defining idea is the format itself: an oversized uncut roll built to be held like a burrito rather than picked up with chopsticks.
The craft is closer to sushi than to a taquería, and that is where it succeeds or fails. The rice has to be properly seasoned sushi rice, vinegared and at the right tackiness, because rice that is too dry will not hold the roll and rice that is gummy turns the whole thing pasty. It is spread over a nori sheet, often on a bamboo mat, with the fillings laid in a defined line so the roll is even end to end: raw or cooked fish or another protein, avocado, cucumber, pickled vegetables, sometimes tempura crunch, with sauces threaded in rather than flooded. The roll is wrapped tight, seam-side down, so the nori seals against the rice and the cylinder holds without being cut. A good one is balanced and structurally sound, the nori still with some integrity, the fillings centered. A weak one is overstuffed so the nori splits, under-seasoned so the rice tastes flat, or sauce-soaked so the seaweed goes slack and the whole thing slumps apart in the hand.
The variations track standard sushi-roll logic dropped into the larger form. A tempura-shrimp build leans crunchy and rich; a spicy-tuna build leans soft and heat-forward; a vegetable build trades fish for avocado, cucumber, and pickle. Slice the same construction into rounds and serve it on a plate and it stops being a burrito-format object and reverts to maki, which deserves its own article rather than being crowded in here. Keep the wrap-and-hold idea but return to a flour tortilla loaded with rice, beans, and griddled meat and you are back at the conventional super burrito this borrows its shape from, which deserves its own article rather than being crowded in here.