In a mixing bowl, combine the softened cream cheese, shredded cheddar cheese, diced jalapenos, ranch dressing, garlic powder, onion powder, salt, and black pepper. Mix until well combined.
Place the chicken breasts in the slow cooker. Pour the cheese mixture over the chicken, making sure the chicken is well-coated.
Cover the slow cooker and cook on low for 6 hours, or until the chicken is tender and easily shred with a fork.
Once cooked, shred the chicken in the slow cooker using two forks and mix it well with the cheesy sauce.
Serve warm, garnished with chopped green onions if desired.
For a spicier dish, add more jalapenos or include some diced serrano peppers.
This dish pairs well with rice, tortillas, or can be served as a filling for tacos.
Leftovers can be refrigerated for up to 3 days or frozen for later use. Just reheat before serving.