Season the chicken with adobo (or salt), then place in the crock pot and top with salsa, garlic powder and 1/2 tsp cumin.
Cover and cook LOW for 4 hours. When cooked, remove the chicken and set on a large plate; shred with two forks. Pour the liquid into a bowl and reserve, then place the shredded chicken back into the crock pot, adjust salt to taste and add remaining 1/4 tsp cumin.
Pour 3/4 cup of the reserved liquid back into the crock pot and cover until ready to serve.