Add all ingredients from the "base" to the slow cooker along with 1/4 cup of water. Stir to combine making sure the chicken is covered with the mixture. Secure the lid of the slow cooker and cook on low for 8 hours.
Near the end of the cooking time, cook the two cups of rice according to the package directions
After 8 hours of cooking, carefully remove the lid of the slow cooker. Stir with a fork to shred the chicken (it should be super tender and will shred easily). Build the taco bowls by placing rice on the bottom, then the taco chicken mix, shredded cheese, green onions and fresh cilantro.
Combine all ingredients from the "base" list to a glass casserole dish, sprayed with cooking spray. Cover chicken breasts in mixture and bake at 425 degrees for 30-40 minute or until chicken is thoroughly cooked. Remove chicken to a cutting board when cook time is up and shred with two forks. Return shredded chicken to casserole dish and combine with other cooked ingredients. Serve by spooning cooked rice into a bowl and topping with chicken mixture. Garnish with shredded cheese, green onions and cilantro.