Vegetable Tian in my new Le Creuset Au Gratin Dish

I received this beautiful Le Creuset Cast Iron Au Gratin Dish as a gift and couldn't wait to try it out!
This recipe is a great way to get an assortment of fresh vegetables into your diet and it tastes delicious! The original recipe came from one of Ina Garten's excellent books. But I change it up a bit depending on what vegetables and cheese I have available. Eggplant, green tomatoes and different squash have found their way into this dish, so throw in whatever your family likes.

2 large red tomatoes, sliced
2 large green tomatoes, sliced
2 potatoes, sliced
1 large yellow onion, sliced
1 large or 2 small zuchinni squash, sliced
Fresh garlic to taste
Olive oil
Kosher salt
Fresh ground black pepper
Thyme
4 oz grated cheese of your choice- French comte cheese or sharp cheddar cheese are my favorites.
A casserole dish or baking pan.
A skillet to cook onions

Preheat your oven to 375 and brush your casserole dish with a bit of olive oil. In a skillet, heat about 2 tbsp of olive oil and lightly cook the onions and garlic until the onions become translucent. Spoon the onions and garlic into the bottom of your casserole dish. Layer the thinly sliced vegetables alternating the colors until you fill the dish. Sprinkle with salt, pepper and thyme. Drizzle a bit of olive oil over the top and bake covered with aluminum foil for 40 minutes or until the potatoes are tender. Remove from the oven and sprinkle the grated cheese over the vegetables. Bake uncovered for an additional 30 minutes.

On it's way to the oven.

Before adding the cheese.