Add cream of mushroom soup and mushroom broth to a medium sized saucepan over medium heat and bring to a simmer. Reduce heat, stir in parmesan cheese, black pepper, lemon juice, and thyme. Allow creamy sauce to cook 10-12 minutes, or until slightly thickened.
Prepare sauteed mushrooms. Add butter to a skillet over medium heat. Stir in button mushrooms and garlic and saute until tender, about 5-7 minutes. Pour mushroom and garlic mixture into creamy mushroom sauce and stir to combine.
Cook rigatoni pasta according to package directions.
After draining pasta, return noodles to empty pasta pot. Drizzle cooked pasta with creamy mushroom sauce and stir to combine.
Divide pasta into bowls and garnish with fresh parsley and parmesan cheese. Enjoy!