Season chicken with Italian seasoning, garlic powder, paprika, salt, and pepper.
Heat olive oil in a large skillet over medium-high heat.
Cook chicken for 5-7 minutes per side until golden brown and cooked through (165°F internal temp).
Remove chicken from the pan and cover with foil.
In the same skillet, melt butter over medium heat.
Add garlic and red pepper flakes, cooking for 30 seconds.
Add shrimp and cook for 2-3 minutes per side until pink and opaque.
Pour in lemon juice; simmer for 1 minute.
Remove shrimp and set aside.
In the same pan, add heavy cream and chicken broth, bringing to a gentle simmer.
Stir in Parmesan and butter until melted and smooth.
(Optional) Add cornstarch slurry to thicken sauce.
Return chicken and shrimp to the pan, spoon sauce over.
Garnish with parsley and serve immediately.