Preparation

1. Preheat oven to 375 F. Spray or brush a 2-quart baking dish with olive oil.
2. Warm 2 teaspoons of olive oil in a medium skillet over medium heat. Add the sliced onion and cook until softened and slightly golden. Stir in a pinch of salt, the water and thyme. Set aside to cool.
3. While the onions are cooking, slice the zucchini and summer squash into thin rounds - about 1/4-inch thick. Core and slice the tomatoes in half lengthwise, then into half moons, about 1/4-inch thick.
4. Stack the zucchini, onions, tomatoes and yellow squash into the baking dish with their colorful sides up, alternating to create many lovely layers until all of the vegetables have been added. Brush with remaining olive oil. Season with salt and pepper. Bake in oven for 40 minutes, rotating the dish halfway through the cooking time. Sprinkle the cheese over the top and return to oven for an additional 10 minutes. Allow to rest slightly before serving.