Preheat your oven to 425°F (220°C) for roasting the broccoli.
In a small bowl, combine the olive oil, lemon juice, minced garlic, salt, and black pepper to form the marinade.
Pat the chicken breast dry and coat it evenly with the marinade. Let it sit for 10-15 minutes to absorb the flavors.
Place the chicken breast in a hot, non-stick skillet over medium-high heat. Sear each side for about 2-3 minutes until golden and crispy.
Transfer the chicken to a baking sheet.
Meanwhile, toss the broccoli with a little extra olive oil, salt, and pepper, and spread it out on another baking sheet.
Place the broccoli in the preheated oven and roast for 15-20 minutes until tender and slightly charred at the edges.
Bake the chicken in the oven for an additional 10-12 minutes or until fully cooked (internal temperature reaching 165°F).
Remove both the chicken and broccoli from the oven, plate them together, and serve immediately with an extra squeeze of lemon if desired.