Rinse the rice in a sieve under cold running water until it is clear. Drain well. Add the water and rice to a pan and leave to absorb for approx. 30 mins.
Bring the rice to the boil with the lid off, reduce the heat until the water has evaporated, leaving small indentations on the surface of the rice, cover and leave to absorb over a low heat for approx. 10 mins, do not lift the lid.
Warm the sugar, rice vinegar and salt in a small pan, stirring until the sugar has dissolved.
Pour the rice into a wide-bottomed bowl, drizzle with the warm liquid, mix carefully with a fork for approx. 3 mins. while fanning. Cover the rice with a damp cloth and leave to stand for approx. 15 mins.
Cut the meat into pieces approx. 2 cm wide and approx. 5 cm long. Combine the soy sauce, sesame oil and garlic, coat the meat in the marinade, cover and marinate for approx. 1 hr.
Peel the carrots into strips using a peeler. Heat the oil, brown the meat all over for approx. 1 min. Stir in the sesame seeds. Combine the yoghurt and wasabi. Drain the ginger and set aside, along with the carrots.
Place one nori sheet (rough side up) on a bamboo mat or piece of cling film. Set aside 1/3 of the rice. Place 1/4 of the remaining rice on the nori sheet, leaving a gap of approx. 2 cm at the top.
Spread 1/4 of the wasabi yoghurt, meat, ginger and carrot lengthwise in the centre of the rice. Repeat this step three more times. Roll up the filled nori sheets, roll them between your hands until everything holds together. Fill the ends of the rolls with the reserved rice, press firmly.
Drizzle a little water over the rolls, turn 2 rolls in the pistachios and 2 rolls in the allspice. Cut the rolls in half using a very sharp, wet knife.