Heat oil in a 10-inch cast-iron skillet coated with cooking spray over medium heat. Add onion, bell pepper, and garlic; sauté 5 minutes. Arrange potato over onion mixture; sprinkle with salt, black pepper, and red pepper. Cover, reduce heat to medium-low, and cook 20 minutes or until potato is tender.
Preheat broiler. Combine eggs, parsley, and chives in a medium bowl; stir well with a whisk. Pour over vegetables; cook over medium heat 10 minutes or until almost set. Top with tomato; broil 4 minutes or until browned and set. Garnish with parsley sprigs, if desired.