Heat up a skillet over medium high heat (make sure the pan has a lid). Season the chicken breasts all over with salt and pepper, then place the chicken skin side down directly onto the pan.
Cook for 2 minutes on each side, then remove the chicken breasts temporarily to a plate. There should be some brown bits on the bottom of the pan now. Deglaze the pan by adding the chicken broth, scraping up the brown bits from the pan. Add the fire roasted tomatoes, cumin, chili powder, oregano, coriander, and bay leaf.
Put the chicken breasts back into the pan and turn the heat down to medium. Put the lid on and simmer the chicken for 20-30 minutes, until the chicken is cooked (I cook mine to 160 degrees F).
After the chicken has cooked, let it rest for at least 10 minutes before shredding, otherwise all the juices will run out of the chicken. In the meantime, turn the heat to high and reduce the spiced tomato sauce until it reaches the consistency you like (this should be 5-10 minutes). Make sure to stir often so it doesn’t burn. Toss the shredded chicken to coat in this sauce, and serve.