Using a little olive oil, lightly oil (or spray with a fine mist of oil) a large casserole dish and set aside. In a large bowl, place the zucchini, summer squash, parsley, tamari, and garlic, and toss gently to combine. Season to taste with crushed red pepper flakes, salt, and pepper, and toss again. Transfer the mixture to the prepared casserole dish and bake at 350 degrees for 20 minutes. Remove the casserole dish from the oven, pour the diced tomatoes over the top, and stir gently to combine. Return the casserole dish to the oven and bake an additional 15-20 minutes or until vegetables are soft. Remove the casserole from the oven. Taste and adjust seasonings, as needed.
Serves 6-8