Preheat oven to 350 degrees Fahrenheit, setting your rack on middle position.
Heat the olive oil in a frying pan set over medium heat and add in the zucchini, tomatoes, chives and basil. Cook until the vegetables soften and just start to brown, about 7 – 10 minutes.
Spray the bottom of a round baking dish (approximately 8 inches in diameter) with cooking spray and place the vegetables into the baking dish. Spread them so that they are evenly dispersed in the baking dish.
In a small mixing bowl beat the eggs. Add the milk, feta, salt and pepper and mix well.
Pour the egg mixture into the baking dish, over the vegetables.
Place in the preheated oven, on the middle rack, and bake for 15 – 20 minutes, until the eggs are set.
Remove from the oven and serve.
Enjoy!