For the spinach maki, defrost the spinach. Put the rice in a sieve and rinse until the water is completely clear and clean.
Place in a saucepan with 175 ml of water and boil for 10 minutes – with lid. Turn off the heat and let it swell for half an hour with the lid on.
After the swelling time, stir in rice vinegar, sugar and salt and mix well. Place the first nori sheet smooth side down on the bamboo rolling mat, wet your hands with vinegar water and form a handful of rice into a ball. Press firmly, then transfer to the nori sheet, pressing on top and spreading evenly – leaving a 2 cm border at the top.
Squeeze the spinach and place a third of it on the bottom edge. Spread some wasabi over the spinach and roll up tightly with the help of the mat. Brush the top edge with a little vinegar water and roll or tape closed.
Do exactly the same with the other two nori sheets. Now cut the sushi roll into even rolls with a sharp knife.