1. Preheat oven to 350 degrees F. Grease a 9x13 pan and set aside.
2. In a large bowl whisk together the eggs, oil, Romano cheese, parsley, salts, oregano and garlic powder. Whisk in the onion, and then the Bisquick. With a rubber spatula, gently stir in the sliced zucchini, being careful not to break up the slices. Turn the mixture into the pan and smooth the top.
3. Bake until puffed and golden brown, 25 to 30 minutes. Let cool to warm room temperature before serving.