1Wash the rice under running water several times, and let drain in a colander for about 40 minutes.
2Then, heat the rice in a saucepan of boiling water, let a little bit of the water evaporate, put the lid on the pan, and let the rice simmer for about 5 minutes (be careful not to let it stick to the bottom of the pan). Remove from heat, and cool completely.
3Cut the ends of the zucchini, wash thoroughly and cut thin slices of the zucchini with a potato peeler and grill. Be careful not to grill too much so that the zucchini slices do not fall apart.
4While the rice and zucchini cool, place the avocado in a small bowl, and use a fork to crush. Add salt, the juice of 1/2 a lemon, and finally, chopped parsley.
5Assemble the sushi, as pictured.
6First, add the rice, then the avocado, and then roll up the zucchini slices carefully.
7Sprinkle some black sesame seeds on top to add a very oriental touch.
8For the sauce, mix plain yogurt, a dash of olive oil, a tablespoon of old Dijon mustard, salt, pepper to taste, and finally a grain of black mustard.