If you were in Denver this past week, you would have found yourself scrambling to harvest the final produce from your garden before the snow and freezing temperatures hit. And you might just now be staring at too many tomatoes and zucchini, not know what to do with them all. This is a simple gratin that really can use any vegetables you like. Spray a baking dish with cooking spray and then layer it up. I used zucchini, tomatoes, and onions, with a layer of mozzarella cheese and a sprinkling of Parmesan every round. Cover and bake at 375 degrees until the vegetables are soft and the cheese is bubbly, about 20 minutes. Leftovers can be easily microwaved for a quick vegetarian lunch.