Place the shrimp in mirin and let marinate.
Rinse cucumber and cut into about 7 cm (approximately 3 inch) long and 5 mm (approximately 1/4 inch) wide strips. Rinse and trim scallions and cut into 7 cm (approximately 3 inch) strips and halve lengthwise.
Rinse cilantro, shake dry and remove leaves.
Mix mayonnaise with the soy sauce.
Moisten your hands with water and vinegar and form 4 oblong portions with the rice.
Cut the nori sheets in half diagonally and take 1 sheet with the smooth side down in the left hand. On the top half place 1 rice portion and spread with a little wasabi paste. Top each with some cucumber, scallions, cilantro leaves, drained shrimp and mayonnaise. Press firmly and roll up nori over fillings.