Preheat oven to 450° .

Mix the cheese, 1 teaspoon thyme and breadcrumbs, set aside.

Coat baking dish with cooking spray.  Trim off  a little from the bottoms of each onion half and remove the peeling.  Arrange the halves, cut side down in baking dish.

In a bowl, mix the beef broth, 2 teaspoons thyme, and worchestershite sauce. Pour this mixture over the onions and cover with foil. Bake at 450° for about 30 minutes. After 30 minutes, uncover and continue baking for another 30 minutes.

Remove onions from the oven and if they are tender when pierced with a knife top with some of the cheese/breadcrumb mixture and bake for another 5-10 minutes until cheese has melted and browned.