Preheat oven to 450 degrees. Start by cooking the vegetables: Spray a very large non-stick skillet with cooking spray. Add vegetables to skillet along with 1 cup water (you may need more if you are using fresh veggies rather than frozen.) Turn heat to medium high, and place cover on pan. Cook until vegetables are just tender, stirring occasionally, and removing cover after about 3-5 minutes to let the water evaporate.* (Although, you may have to actually add about ½ cup water if vegetables are not almost done cooking at this point, but the water has dried up, so the veggies don’t burn in the pan). *
When vegetables are tender, but still a bit crisp, drain water if there is any left in the pan (although, it should be cooked off at this point), and place in a medium bowl. (I like to do this step the night before a big breakfast, so my veggies are ready to add to the eggs the next morning! Saves lots of time!)
Meanwhile, in a large bowl, whisk together the eggs, Parmesan, and the seasoning. Gradually stir in vegetable mixture one spoonful at a time to the eggs so that the vegetables will not cook the eggs.
Bake for 35 to 45 minutes or until frittata is cooked through and slightly golden brown on top. Cut into eight equal servings and enjoy!