Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.
Toss the broccoli florets with olive oil, minced garlic, sea salt, and black pepper on the prepared baking sheet.
Roast the broccoli for 15-20 minutes until the edges are crispy and slightly charred.
While broccoli roasts, whisk together lemon juice, a pinch of salt, and pepper in a small bowl to create a marinade.
Coat the chicken breast in the marinade and let it sit for 5 minutes.
Heat a grill pan or outdoor grill over medium-high heat and lightly coat with oil spray.
Grill the chicken for 6-7 minutes per side or until the internal temperature reaches 165°F.
Let the chicken rest for 3 minutes before slicing into strips.
Fluff the pre-cooked quinoa and place it in a bowl.
Top the quinoa with the sliced grilled chicken and roasted broccoli florets.