Place the chicken breasts in the slow cooker and season with chili powder, smoked paprika, garlic powder, cumin, salt, and black pepper.
Add the corn over the chicken, cover, and cook on LOW for 5–6 hours or HIGH for 3–4 hours until the chicken is tender.
Remove the chicken from the slow cooker and shred it using two forks.
Return the shredded chicken to the slow cooker and add the cream cheese, sour cream, mayonnaise, and lime juice.
Stir until the cream cheese melts and the mixture becomes smooth and creamy.
Mix in the cotija cheese, cilantro, and jalapeño if using, then cook for another 10 minutes.
Serve warm over rice, in tortillas, or in burrito bowls with your favorite toppings.