MIX cream cheese spread, 2 Tbsp. milk and garlic powder until blended.
HEAT oil in large skillet on medium-high heat. Add red peppers and onions; cook and stir 4 to 5 min. or until crisp-tender. Stir in peas; cook 3 to 4 min. or until heated through, stirring frequently. Add shrimp, black pepper and remaining milk; cook and stir 3 min. or until heated through. Add cream cheese mixture and lemon zest; cook and stir 2 min.
SERVE over rice.