Slice each chicken breast in half horizontally to make 4 thinner cutlets and pat dry; season both sides with salt, garlic powder, oregano, black pepper, and chili powder.
Heat 1 tablespoon olive oil in a large skillet or cast-iron pan over medium-high heat.
Add 2 tablespoons of the butter to the hot pan, then add the seasoned chicken. Cook 4–5 minutes per side until browned and cooked through (no pink inside).
Remove the cooked chicken to a plate; lower heat to medium and add the remaining 2 tablespoons butter, minced garlic, Italian seasoning, and crushed red pepper to the pan. Sauté 30–60 seconds until fragrant.
Add the broccoli florets and pour in the water or chicken stock and lemon juice; toss and cook 2–3 minutes until broccoli is just tender but still bright green.
Return the chicken to the pan to warm and coat with the garlic butter sauce, then serve immediately.
