Rinse chicken and pat dry. Place in the lightly oiled crock of a slower cooker. Set aside.
In a pint jar, place the water, white vinegar, cumin, chipotle chile powder or chipotle chile in adobo, minced garlic, Italian salad dressing mix, and Ranch dressing mix. Put the lid on the jar and shake until the ingredients are well blended.
Remove lid from jar and add salad oil. Put lid back on jar and shake to blend oil well with the other ingredients. Pour over chicken.
Cover slow cooker and cook on high 4-5 hours. Shred chicken with two forks and allow to remain in slow cooker for an additional 30 minutes.
Remove chicken from slow cooker with a slotted spoon to allow juices to drain away. Keep cooking juices to moisten chicken as desired. Dress chicken with chopped cilantro and lime wedges, optional.
May be used in tacos, burritos, enchiladas, salads, or other Mexican dishes of choice.