I found this recipe from the For the Love of Cooking Blog. I made it for dinner on Saturday night and everyone is still raving abou it.
Tomato, Zucchini, Squash and Caramelized Onion Gratin
• 6-7 large Roma tomatoes, sliced
• 1 large zucchini (or 2 small ones), sliced
• 1 large yellow squash (or 2 small ones), sliced
• 1 tsp olive oil
• 1 onions, sliced
• 1 clove of garlic, sliced very thin
• 1/4-1/2 cup of Parmesan cheese, grated
• 1/2 tsp dried basil
• 2-3 leaves of basil, chopped for garnish
Preheat the oven to 375 degrees. Coat a large and deep baking dish (I used a large corning ware casserole dish) with olive oil cooking spray. Slice the zucchini, yellow squash, onion and tomatoes into thick slices.
Heat the olive oil in a skillet over medium heat. Once the pan is hot add the onion slices and sauté for 15-20 minutes or until golden brown and caramelized- make sure you season with sea salt to taste. Add the garlic to the onions and sauté, stirring frequently for 60 seconds then remove from heat and let cool.
Layer the dish with first tomatoes then yellow squash, a bit of Parmesan then the layer of caramelized onions and garlic, then the zucchini and finally the last layer of tomatoes. I seasoned each layer (except the onions) with a little bit of sea salt and pepper. Top with the remaining Parmesan cheese and sprinkle the dried basil on top and cover with a lid or tin foil.
Bake for 20-25 minutes. Remove the lid or tin foil and broil for 3-4 minutes or until golden brown and crispy on top. Let cool for a few minutes. Garnish with fresh basil. Enjoy.