Boil the chicken breasts with water and a little salt, while removing the foam that forms. Take them out, debone them and tear into coarse pieces. Strain the broth and save it.
Heat oil in a pot, add the finely chopped onions to braise. Add washed and strained rice, fry until it turns glassy. Pour in the chicken broth and leave on the stove for 5 min., while stirring periodically.
Transfer the swollen rice to a tray, distribute the pieces of chicken meat on top, pour in more broth if needed. Bake in a preheated 356°F (180 °C) oven until rice absorbs the liquid. Serve sprinkled with freshly ground black pepper.