Preparation
Cut asparagus spears into 2-1/2 inch thick lengths. Bring a saucepan of water to a boil and cook the asparagus until just tender, about 2 minutes. Drain and place in a bowl.
Preheat the broiler.
Spray a 9 or 10 inch nonstick, ovenproof skillet with cooking spray and set over medium-low heat. Add shallots and cook, stirring, until they begin to brown, about 2 minutes. Add the shallots to the asparagus.
In a mixing bowl, whisk together eggs, egg whites, chives (if using) salt and pepper. Add asparagus/shallot mixture.
Spray skillet generously with cooking spray and return the skillet to the heat. When the pan is hot, pour in the egg mixture and gently shake the pan to evenly distriube the vegetables. Reduce the heat to medium-low and cook until the botom is set, about 5 minutes.
Sprinkle the top of the frittata with Parmesan and place under the broiler to finish cooking, about 1 minute.
Cut into wedges and serve.