Place the chicken breasts in the slow cooker and add the can of Rotel, garlic powder, onion powder, and chopped cilantro; stir to combine.
Cover and cook on low for 5–6 hours, or until the chicken shreds easily with two forks.
Carefully remove the chicken to a cutting board, shred with two forks, then return the shredded chicken to the slow cooker and stir.
Add the cream cheese and lime juice to the slow cooker, cover, and let sit while you cook the onion so the cream cheese softens.
In a small skillet, melt the butter over medium heat. Add the chopped onion and cook, stirring occasionally, until soft and translucent, about 4–5 minutes.
Stir the cooked onion into the slow cooker until the cream cheese is melted and the sauce is creamy and well combined.
Serve the creamy shredded chicken in warmed flour or corn tortillas and top with shredded Colby Jack cheese.