Lay one sheet of nori on a sushi rolling mat with the smooth side facing down and the perforated lines running parallel to the bamboo of the rolling mat.
To make sushi rice, add 2 tablespoons of sushi vinegar to 1 cup of warm short grain rice. Spread 1 cup of sushi rice evenly onto the nori sheet, leaving about ½ inch of room at the top.
Remove the seeds from cucumber slices, and then slice into thin batons. Slice cream cheese into batons of a similar sizes. You'll need enough cucumber batons and cream cheese pieces to stretch from the left side of the nori to the right.
Alight the cucumber batons and cream cheese about ⅓ from the bottom of the nori sheet. Then gently fold up the bamboo mat so the rice shapes around the filling. Gently squeeze the cucumber roll and seal the remaining edge of nori.
Slice the nori roll in half, and then slice each half in thirds or fourths. Serve with a side of soy sauce, wasabi, and/or pickled ginger.