Thinly slice the myoga. Trim the roots of the pea shoots and cut them in half. Remove the seed from the umeboshi and mash it with a knife.

Season the pork slices with salt and pepper. Place myoga and pea shoots on the pork and roll them up tightly. Repeat to make 8 rolls.

Arrange the rolls on a microwave-safe plate, sprinkle sake over them, cover loosely with plastic wrap, and microwave at 600W for 3–4 minutes. Reserve 1 tbsp of the steaming liquid.

Mix the reserved steaming liquid with the sauce ingredients (umeboshi, sugar, ponzu, and sesame seeds) in a bowl.