Whisk together Italian seasoning, chopped thyme, garlic powder, and lemon pepper. Season chicken with half of the mixture. Cook chicken in a greased pan or skillet over medium heat 5-7 minutes on each side until lightly browned and cooked through. Transfer chicken to a plate and cover to keep warm.
Add garlic and mushrooms to pan and stir over medium heat 2-3 minutes until fragrant and mushrooms are tender. Stir in chicken broth, lemon juice, and remaining seasoning mixture. Stir in cream until mixture begins to boil, cook another 2-3 minutes, stirring constantly.
Return chicken to pan and toss in the sauce to coat. Garnish with lemon slices, fresh thyme, and cracked black pepper as desired. Serve hot.