Preheat oven to 400° F.

Spiralize cut the zucchini to make 5 cups of zucchini noodles.

In a skillet preheated to medium heat, melt unsalted butter. Place yellow onion into skillet and cook for a few minutes.

Add the Beef Broth and Worcestershire Sauce, and cook until onions are golden brown (~12 minutes). Stir occasionally to keep the onions from burning.

Spray a 9"x 13" casserole baking dish with non-stick cooking spray. In a large bowl combine zucchini noodles and french onion mixture. Pour the combined onion/zoodles into the dish and garnish the top with the grated cheese.

Place in the middle shelf of the oven and bake for about 20-25 minutes or until golden brown. Remove from oven and cool slightly before serving. Garnish with fresh thyme, and salt & pepper to taste.