Mozzarella, Basil, and Zucchini Frittata

1. Position rack in upper third of oven; preheat broiler.

2. Heat oil in a large broiler-safe nonstick or cast-iron skillet over medium-high. Add onion and zucchini and cook, stirring frequently, until soft, 3 to 5 minutes.

3. Meanwhile, whisk eggs, salt, and pepper in a bowl. Pour eggs over vegetables in pan. Cook, lifting edges to allow uncooked egg from the middle to flow underneath, until nearly set, about 2 minutes. Arrange mozzarella and sun-dried tomatoes on top and place skillet under broiler until eggs are slightly browned, 11/2 to 2 minutes. Let stand for 3 minutes. Top with basil.

4. To release frittata from pan, run a spatula around edge, then underneath, until you can slide or lift it out onto a cutting board or serving plate. Cut into 4 slices and serve.