In a small bowl, combine the salt, black pepper, paprika, and garlic powder. Pat the chicken dry, then season both sides evenly with the spice mixture.
Heat olive oil in a large skillet over medium-high heat. Cook the chicken for 5–7 minutes per side until golden. Transfer to a plate.
Reduce heat to medium. Add butter and cook the garlic for about 30 seconds until fragrant.
Pour in chicken broth and scrape the bottom of the pan to release the browned bits.
Add the heavy cream and let it warm through.
Add black pepper, basil, and oregano and stir to combine.
Whisk in the Dijon mustard and simmer for 3–4 minutes until slightly thickened.
Stir in Parmesan until melted, then add spinach and cook until wilted.
Return chicken to the skillet and simmer 5–8 minutes until fully cooked.
Spoon the sauce over the chicken and serve warm.