In large nonstick skillet, heat 2 teaspoons of the oil over medium heat. Add potatoes; cook, tossing occasionally for 7 minutes.
Add asparagus, salt, tarragon and marjoram; stir to combine. Cover and cook, stirring occasionally until asparagus and potatoes are tender, about 7 minutes.
Meanwhile, in large bowl, whisk together whole eggs, egg whites and Parmesan. Reduce heat under skillet to low. Spoon remaining 1 teaspoon oil around inside edge of pan. Add egg mixture; cover and cook until eggs are set, about 20 minutes.
With spatula, release frittata from pan and slide it onto serving platter. Cut into wedges and serve hot or at room temperature.
A frittata is an Italian omelet that is usually made with whole eggs, but this lightened version is made with fewer egg yolks and more whites to reduce fat and cholesterol.