At the peak of summer, when corn, zucchini, and tomatoes are in abundance, turn this tasty trio into a simple frittata. Feel free to swap in cilantro for basil and other cheeses, such as feta or pepper Jack. It's best warm from the oven, but keeps well for several days in the fridge. Serve leftovers cold or reheat in the oven or microwave.
Preheat oven to 350 degrees F. Grease a 9-inch-square pan with olive oil.
Heat 2 teaspoons olive oil over medium-high in a large skillet. Add the onion and sauté until tender, about 5 minutes. Add the zucchini, corn kernels, and salt, and sauté until tender, about 4 minutes. Remove from heat and stir in the basil and tomatoes.
Transfer the vegetables to the prepared pan and spread them out. Top with half the cheese.
In a medium bowl, whisk together the eggs and milk until blended. Pour over the vegetables. Scatter the remaining cheese over the top and add a light shower of freshly ground black pepper
Bake until the eggs are just set. The top of the frittata should dome and be slightly firm in the center, about 35 minutes.
Cool for 5 minutes before cutting into squares. Cover and store leftovers in the fridge, where the frittata will keep for several days. Reheat in the oven or microwave.