Whisk eggs, water and pepper in small bowl; set aside.
Spray 8-inch (20 cm) non-stick skillet with cooking spray. Heat skillet over medium heat. Add red pepper and onion; cook, stirring frequently, until tender, about 3 minutes. Stir in ham.
Pour in egg mixture. As eggs set around edge of skillet, with spatula, gently lift cooked portions to allow uncooked egg to flow underneath. Cook until bottom is set and top is almost set.
Slip spatula underneath omelette and fold in half. Slide onto plate.