Cut the chicken into bite-sized pieces, and sprinkle with the garlic powder.
Coat a 4-quart pot with cooking spray, and preheat over medium heat. Add the chicken and cook, tossing or turning the pieces occasionally, for about 7 minutes, or until the chicken is no longer pink inside when cut with a knife. Transfer the chicken to a bowl.
Place the rice, salsa, and broth in the pot, and stir to mix. Increase the heat to high, and bring to a boil.
Return the chicken to the pot, reduce the heat to low, and cover. Simmer for 5 to 10 minutes, or until the liquid has been absorbed and the rice is tender. Serve immediately.