In a saucepan heat 2 Tbsp. sake. Add chicken and quickly sauté for 2 min. Strain out the chicken and set aside. To saucepan add water, soy sauce, 2 Tbsp. sake, onion and cook until onions are translucent. Add ginger and let simmer for 2 minutes. Add chicken and peas. Pour eggs over chicken in pot and let it set for 1 minute. Stir once and cover. Turn off heat. Serve in a bowl over rice.
