Slit chicken breast down the middle (do not cut all the way thru). Boil chicken in 2 cups of water. When finished wrap in foil and place on a cookie sheet and bake in the oven at 250 degrees celsius for 10-15 minutes. (This should give you enough time to caramelize the onions and make the sauce).
Remove all chicken broth from pan except for 1/2 cup of the broth, add all ingredients including onion. Stir-fry for a few minutes then put heat on low, cover, and let the onions caramelize.
When onions are brown remove the lid and toss, pour the mixture on top of the chicken, and serve.
You could play with the spices a bit – I might add some basil/thyme next time lol. Enjoy!