Place 3–4 chicken breasts into the slow cooker in a single layer.
Add 1 can of Rotel tomatoes (undrained), 1 tsp garlic powder, 1 tsp onion powder, and 2 tbsp chopped cilantro; stir to combine.
Cover and cook on low for 5–6 hours, until the chicken shreds easily with two forks.
Remove the chicken to a cutting board and shred with two forks; return the shredded chicken to the slow cooker and stir.
Add the 8 oz whipped cream cheese and 1 tbsp lime juice to the slow cooker, stir, then cover and let sit while you cook the onion so the cream cheese softens.
In a skillet over medium heat, melt 1/2 tbsp butter and cook the 1/2 chopped medium yellow onion, stirring occasionally, until soft and translucent, about 4–5 minutes.
Add the cooked onion to the slow cooker, stir everything together until the cream cheese is melted and the sauce is combined.
Serve the creamy shredded chicken in warmed flour or corn tortillas and top with shredded Colby Jack cheese.
