Preheat the oven to 375°F and lightly spray a 4‑quart baking dish with nonstick spray.
Pat the chicken breasts dry with paper towels and arrange them in a single layer in the prepared baking dish; season lightly with salt and pepper.
In a large bowl, beat the cream cheese until smooth, then add the garlic powder, onion powder, cumin, salt, ground black pepper, diced green chiles (with juices), and green enchilada sauce; mix until well combined.
Spread the cream cheese and green chile mixture evenly over the chicken breasts.
Sprinkle the shredded Colby Jack cheese over the top of the coated chicken.
Bake for 30–35 minutes, until the cheese is melted and bubbly and an instant‑read thermometer inserted into the thickest part of the chicken reads 165°F.
Let the dish rest for 5–10 minutes before serving.