To Prep
Cut the cucumber in to thin horizontal strips before removing the seeds. This should leave strips of just the flesh that should be trimmed to fit the hand roll.
Add the sushi vinegar to the cooked sushi rice and gentle fold in to the rice until well incorporated.
Pound the chicken using a meat tenderiser to make it thinner and flat.
Dip into the flour, then the egg and finally the breadcrumbs.
To Cook
In a pan with enough oil to fry, cook the chicken until golden and then drain on paper towels.
When the chicken has cooled slightly, cut it in to sections that are small enough to fit on to the hand roll.
To Make the Roll
Cut nori sheets in half. Place sushi rice and then the lettuce, cucumber and chicken slices onto one side of nori.
Fold the nearest corner of the nori over the filling and start to shape.
The finished hand roll should be shaped conically to prevent any rice from falling out from the bottom.
Sprinkle some tonkatsu sauce over the top and serve!