Preheat the oven to 350°F (175°C) and lightly spray or grease a baking dish.
In a large bowl, combine the shredded chicken, softened cream cheese, sour cream, green chile enchilada sauce, chopped green chiles, taco seasoning, chopped cilantro, and chopped green onions.
Stir the mixture until mostly smooth and evenly combined; small lumps of cream cheese are fine.
Fold in all but 1/4 cup of the shredded Mexican blend cheese, reserving that amount to sprinkle on top.
Transfer the mixture to the prepared baking dish and spread into an even layer. Sprinkle the reserved 1/4 cup shredded cheese over the top.
Bake uncovered for 20–25 minutes, until the dip is hot and bubbly and the cheese on top is melted.
If using optional add-ins, sprinkle the diced onion, diced jalapeños, and drained white beans on top after baking, then serve with chips.