Season the chicken: Pat chicken dry.
Season both sides with salt, pepper, and garlic powder. Lightly dust with flour, shaking off excess. This helps with browning and gives the sauce something to cling to.
Sear the chicken: Heat olive oil and 1 tablespoon butter in a large skillet over medium-high heat.
Add the chicken and cook 4–5 minutes per side until golden and just cooked through. Transfer to a plate and tent loosely with foil.
Sauté the garlic: Reduce heat to medium. Add the remaining 1 tablespoon butter to the same pan.
Stir in the minced garlic and cook 30–60 seconds, until fragrant. Avoid browning the garlic.
Deglaze: Pour in the chicken broth, scraping up any browned bits. Let it simmer for 2–3 minutes to reduce slightly.
Build the sauce: Stir in the cream, Italian seasoning, and Dijon if using.
Simmer gently 2–3 minutes, stirring often. Keep the heat moderate so the cream doesn’t separate.
Add parmesan: Lower the heat. Gradually whisk in the parmesan until melted and smooth.
If the sauce seems too thick, splash in a little more broth. If too thin, let it simmer a bit longer.
Finish with lemon and herbs: Stir in lemon juice, a pinch of red pepper flakes if you like heat, and half the parsley or basil. Taste and adjust salt and pepper.
Return the chicken: Nestle the chicken back into the pan, along with any juices on the plate.
Spoon sauce over the top and simmer 2 minutes to warm through.
Serve: Sprinkle with remaining herbs and extra parmesan. Serve hot with pasta, mashed potatoes, rice, or crusty bread, plus lemon wedges on the side.