BLEND milk, cream cheese, garlic and bouillon cube in blender on high speed 1 min. or until smooth; set aside.
COOK and stir chiles and onions in hot oil in large skillet on medium-high heat 5 min. or until onions are tender. Add cream cheese mixture; simmer on medium-low heat 5 min. or until heated through, stirring frequently.
SPRINKLE with mozzarella; cover. Cook 1 min. or until mozzarella is melted.
