Combine potato, onion and green pepper in a 9-inch microwave-safe pie plate. Cover with microwaveable plastic wrap and microwave at HIGH 4 to 5 minutes, or until potato is tender.
Combine eggs, milk, salt, pepper and garlic powder in a medium bowl; beat slightly. Pour over potatoes in pie plate. Cover with microwaveable plastic wrap and microwave at HIGH 4 minutes, stirring after 2 minutes.