Combine first 5 ingredients. Coat both sides of steaks with cooking spray; rub steaks evenly with thyme mixture.
Place steaks on rack of a broiler or roasting pan coated with cooking spray; bake at 450 for 8 minutes on each side or until desired degree of doneness.
Remove from oven; keep warm.
To prepare gravy, heat oil in a large nonstick skillet over medium-high heat.
Add 1/2 teaspoon thyme, mushrooms, and 4 garlic cloves; cook 5 minutes or until mushrooms are tender.
Add broth and wine; bring to a boil. Cook until reduced by half (about 4 minutes).
Combine water and cornstarch in a small bowl, stirring with a whisk.
Add cornstarch mixture to pan; bring to a boil. Cook 1 minute or until slightly thickened, stirring constantly.