In a large mixing bowl, mix together cream cheese, mayonnaise, and BBQ sauce.
Stir in the mozzarella cheese, salt, garlic powder, red onion, cilantro, and chicken.
Spread the dip mixture into the bottom of a 2-quart baking dish (or 8x8 dish) in an even layer. Sprinkle the cheddar cheese all over the top.
Bake for 20 to 25 minutes or until cheese on top is melted and bubbly.
Remove the dip from the oven. Drizzle some BBQ sauce on top and then sprinkle with extra red onion and cilantro. Serve warm with chips for dipping.
Notes
I usually use a rotisserie chicken from the store to make this dip. You could also cook off a couple of chicken breasts ahead of time and use that instead.