Preheat the oven to 350°F (175°C) and lightly spray a baking dish with nonstick spray.
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 until mostly smooth and evenly mixed.
Stir in three-quarters of the shredded Mexican blend cheese, reserving the remaining 1/4 cup to sprinkle on top.
Transfer the mixture to the prepared baking dish and smooth the top; sprinkle the reserved cheese evenly over it.
Bake uncovered for 20–25 minutes, until the dip is hot and bubbly and the cheese 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.