Preheat a grill or grill pan over medium-high heat.
Season the chicken breast with your preferred spices (such as salt, pepper, and a squeeze of lemon, if desired).
Grill the chicken for about 6-7 minutes per side until fully cooked and the internal temperature reaches 165°F.
While the chicken is grilling, preheat your oven to 400°F for roasting the broccoli.
Toss the broccoli with a light drizzle of olive oil (reserve a portion of the olive oil for later use), salt, and pepper, and spread onto a baking sheet.
Roast the broccoli in the preheated oven for about 15-20 minutes until tender and slightly charred.
Meanwhile, cook the quinoa by rinsing it under cold water. Place the 20g of quinoa in a small saucepan with water (typically a 1:2 ratio), bring it to a boil, then lower the heat, cover, and simmer for about 12-15 minutes until the water is absorbed.
Once all components are ready, plate the grilled chicken alongside the roasted broccoli and a serving of quinoa. Drizzle any reserved olive oil over the dish to finish and add extra flavor.