1cuphalf and half (or a combination of milk and cream)
Position a rack in the center of the oven and preheat to 375º.
In a 6" cast iron (or other ovenproof) skillet, heat the oil over medium heat. Add the onion and saute until golden and tender, about 10 minutes. Add the zucchini and saute until tender and beginning to brown, 8-10 minutes. Add the 1/4 teaspoon salt and the corn kernals and saute one more minute, then remove from the heat.
Layer the mozzarella, goat cheese, basil and cherry tomatoes over the top.
In a large measuring cup, whisk together the eggs, half and half and 1/2 teaspoon of salt until smooth. Pour into the skillet.
Bake the quiche until puffed, golden and set, about 20 minutes. Let cool a few minutes before serving.
Nutritional values are based on one of two servings.