In a bowl, with a wire whisk or fork, beat eggs, black pepper, 1/3 cup water and 1/2 tsp. salt until blended.
Dice onion, green bell pepper and ham.
Cut each mushroom in half.
Cut tomatoes into wedges.
In a 12" skillet over medium high heat, in 1 tbsp. hot salad oil cook onion, bell pepper and 1/4 tsp. salt until tender. Add ham and heat through.Remove to small bowl;keep warm.
In same skillet, in 1 tbsp. hot oil, cook mushrooms until golden. Remove to another bowl; keep warm.
In the same skillet over medium heat, heat 2 tbsp. salad oil. Pour egg mixture into skillet; cook until set around edges. With metal spatula, gently lift edge as it sets, tilting to allow uncooked portion to run under the omelet. Shake skillet, occasionally to keep omelet moving freely in the pan.
When omelet is set but still moist, spoon ham mixture over half the omelet. Tilt skillet and, with spatula, fold omelet in half; slide onto heated platter.
Top with mushrooms. Garnish platter with parsley sprigs and tomato wedges.
