Summer Squash Gratin without parmesan butter

zest of one lemon 1 1/2 lbs summer squash or 1 1/2 lbs zucchini , cut into 1/6th-inch slices 1/2 teaspoon fine grain sea salt 1/4 cup fresh oregano leaves 1/4[...]

2 cups small-curd nonfat cottage cheese or 2 cups low-fat cottage cheese 1 1/2 lbs summer squash (can be yellow, green or a mixture) salt , to taste 1/2[...]

3 tablespoons olive oil , plus about 1/2 teaspoon olive oil , for the baking dish 1 medium onion , minced 2 lbs zucchini or 2 lbs yellow squash, finely diced[...]