In a swallow saucepan warm the olive oil and wilt the vegetables and the garlic for a couple of minutes over low heat. Add the crayfish, give everything a good toss and wait for 1-2 minutes until the crayfish changes colour -it turns pink. Then transfer the crayfish to a platter.
Add the orzo pasta to the pan and stir it to get it well coated by the food juices. Pour in 10 tea cups of water and simmer the pasta over low heat for 15 minutes, stirring occasionally. Season with salt and pepper and finally, towards the end of cooking time, add the crayfish.
Put the sesame paste in a small mixing bowl and, while stirring, add 3 tablespoons of water and the juice of a lemon to get it thinner. Then add some broth from the food with a procedure similar to the egg and lemon sauce. Remove the crayfish orzo from the heat and leave it to rest for a couple of minutes. Finally add the sesame paste mixture, stir and serve. Sprinkle with some finely chopped parsley according to taste.