The protein content is high and the price is right, making eggs a nutritional bargain. While the yolk does contain cholesterol and some fat, you also get valuable quantities of vitamin A, riboflavin, folate and niacin, as well as some iron, B vitamins, phosphorus and vitamin E.
Whisk together the whole eggs and egg whites in a large bowl. Whisk in the rice, Parmesan, thyme and salt and pepper to taste.
Heat the oil in a 23 cm flameproof frying pan over moderately high heat. Fry the onion for 5 minutes or until translucent. Pour in the egg mixture and sprinkle with the capsicum. Cook, without stirring, for 15 minutes or until the eggs are set around the edges and almost set in the centre. Meanwhile, preheat the griller.
Grill the frittata 15 cm from the heat for 1 to 2 minutes or until the top is set. Serve hot.