Once the breast is cut into smaller fillets, mix in a bowl half the olive oil along with the chicken stock, until a mixture is made and the chicken is dipped. Put the fillets in a non-stick pan until they are evenly browned. Transfer the fillets to a saucepan and, in the pan, add the onion and sauté it in medium heat. Then mix the onion with the chicken. Put the pot on medium heat and add 1 cup of hot water. Simmer for 20 minutes, add zucchinis and chopped green onions, plus freshly ground pepper and salt if necessary.
Prepare the egg yolk by whipping the egg whites, add the yolks, the juice from 2 lemons and finally the hot liquid from the pan.
Pour in the egg sauce, and keep churning until it has been incorporated into the food.