Cook tortellini according to package’s instructions, set aside. Season chicken with salt and pepper, toss in 1/3 cup flour, and add to a greased pan over medium heat. Cook 5-7 minutes on each side until chicken is cooked through and browned. Transfer to a plate and cover to keep warm.
Add butter to pan and stir until melted. Add mushrooms, garlic, and parsley and continue to stir for 2-4 minutes until mushrooms are tender and garlic is fragrant. Sprinkle flour over mushrooms and stir until coated.
Add marsala wine and lemon juice to pan and stir 5-6 minutes longer, stirring throughout until sauce is thickened.
Add chicken and tortellini and cook until tortellini is heated through (3-4 minutes). Season with salt and pepper to taste, garnish with herbs (parsley or thyme are my favorites) and serve immediately.