Season the chicken. Pat the chicken dry with paper towels. Toss with 1 teaspoon salt, 1/2 teaspoon black pepper, and the Italian seasoning. Dry chicken browns better, so don’t skip this step.

Sear in batches. Heat 1 tablespoon olive oil in a large skillet over medium-high. Add half the chicken in a single layer. Sear 2–3 minutes per side until golden and mostly cooked through. Transfer to a plate and repeat with remaining oil and chicken.

Sauté the garlic. Reduce heat to medium. Add butter to the empty skillet. When melted, add minced garlic. Stir 30–45 seconds until fragrant. Don’t let it brown.

Deglaze and build the sauce. Pour in the chicken stock and scrape up browned bits from the pan. Simmer 1–2 minutes to reduce slightly. If using red pepper flakes, add them now.

Add the broccoli. Stir in broccoli florets and a pinch of salt. Cover the skillet and cook 3–4 minutes (fresh) or 5–6 minutes (frozen), until crisp-tender. If the pan looks dry, splash in more stock.

Return the chicken. Add the seared chicken and any juices back to the skillet. Toss to coat in the sauce and cook 2–3 minutes, until the chicken is cooked through.

Finish with Parmesan and lemon. Turn heat to low. Stir in Parmesan until it melts and lightly thickens the sauce. Add lemon juice for brightness. Taste and adjust salt and pepper. If you want it creamier, swirl in a bit of heavy cream.

Serve. Garnish with chopped parsley and extra Parmesan. Serve as is, or spoon over rice, pasta, quinoa, or mashed potatoes.