For the Tempura dough, mix 100 g Tempura flour, egg yolk and 1⁄4 l cold water. Do not stir too hard, the dough may be a little lumpy. Put it in the fridge, then it will be nice and crispy when baked out.
For the sesame cream, mix mayonnaise, soy sauce and sesame oil.
Wash the asparagus, cut the ends off generously. Blanch in little water for about 2 minutes. Lift out and dab dry. Cut salmon into 4 longish pieces (2-3 cm wide and the length of a nori leaf).
Make a longitudinal cut to the middle of each piece of salmon and place 1 asparagus spear in each. Spread wasabi very thinly on each one.
Line a bamboo mat with cling film. Cut nori leaves in half lengthwise. Place each 1⁄2 nori leaf on the bamboo mat with the rough side facing upwards. Put 1 filled piece of salmon on top. Roll up firmly using the bamboo mat.
Do not wrap the film in the process. Form 4 rolls in this way. Flour the rolls and turn them over at high temperature.
Heat the oil in a wide pot to approx. 180 °C (it is hot enough as soon as bubbles rise from a long wooden skewer) or in a deep fryer. Bake the rolls one by one in it for 2-3 minutes, only the outer layer should be baked golden brown, leaving the salmon raw.
Bake the other 3 rolls in the same way.
Cut each roll into 6 pieces and arrange with sesame cream. Add soy sauce, wasabi and sushi ginger.