If using fresh onion, heat oil in a pan, add the onion, and stir over low heat until absolutely soft. If using Frozen Melted Onion, place it in a pan over low heat until heated through.
Stir curry powder into the onion. Raise the heat under the pan. Add the chicken. Stir until coated with the onion spice mixture, and let brown slightly. Add water.
Simmer until chicken is cooked through, and sauce thickens - about five minutes. (This may be a little longer if you increase the recipe.)