Peel the beetroot, then spin on a Japanese slicer to produce a long ribbon. Roll the ribbon up tightly and place in a medium vacuum bag with the vinegar. Seal in a chamber vacuum sealer on full to remove any air, and then refrigerate for 3 hours.
Remove the beetroot and drain off the excess vinegar. Roll back up tightly and then cut the beetroot roll into thin slices to make 8 ribbons.