Cook the sushi rice using the package instructions. Once cooked, dissolve the sugar in the vinegar and stir through the rice.

Combine the tinned tuna with the mayo and furikake.

Once the rice is cool enough to handle mould the onigiri, adding the tuna filling between layers of rice.

Place the moulded rice on to a tray and wrap in the nori, using a stencil to cut out into a design if desired.