Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.
Toss the broccoli florets with one teaspoon of olive oil and a pinch of sea salt on the prepared baking sheet.
Roast the broccoli for 15-20 minutes until the edges are tender and slightly charred.
While the broccoli roasts, season the chicken breast with garlic powder, salt, and black pepper.
Heat a grill pan or outdoor grill over medium-high heat and lightly coat with a tiny bit of oil if needed.
Grill the chicken for 6-7 minutes per side, or until the internal temperature reaches 165°F.
In a small bowl, whisk together the remaining teaspoon of olive oil and the lemon juice.
Toss the warm, cooked quinoa with the lemon-oil mixture to infuse flavor.
Slice the grilled chicken and serve it atop the quinoa with the roasted broccoli on the side.