Use a rolling pin to lightly crush the cucumbers, trim the ends, and cut them into halves. Cut the shiso leaves in half and remove the stems. Remove the seed from the pickled plum and mash it into a paste.

Lightly dust one side of each pork slice with flour. Place a slice of pork on a flat surface, add half a shiso leaf, a small portion of mashed plum, and a piece of cucumber. Roll tightly and press gently to secure. Repeat for all 8 rolls.

Heat salad oil in a frying pan over medium heat. Place the rolls seam-side down and cook, turning occasionally, until evenly browned and cooked through.