TURN crockpot to low heat. To the pot of the crock pot add coconut milk and whisk in seasonings. Place chicken breasts, tomatoes, bell pepper and onion into pot and cover with lid. Cook 4-5 hours, or until chicken is fork tender.
REMOVE chicken breasts and shred using two forks. Return to crockpot and stir to coat in sauce. Serve over cauliflower rice and top with chopped cilantro.
ALTERNATE INSTANT POT METHOD:
ADD all ingredients except cilantro and cauli rice to instant pot. Close lid and vent. Set to manual pressure for 20 minutes. Continue with step 2 above