Preheat your grill or grill pan over medium-high heat and lightly oil the grates.
Season the chicken breast with salt, black pepper, and garlic powder on both sides.
Grill the chicken for about 5-6 minutes per side or until fully cooked and the internal temperature registers 165°F.
While the chicken is grilling, preheat your oven to 425°F for the broccoli. Toss the broccoli with olive oil, a pinch of salt, and pepper, then spread it on a baking sheet.
Roast the broccoli in the oven for about 15-20 minutes, stirring once halfway through, until the edges are slightly crispy.
Prepare the quinoa if not already cooked. Warm it gently on the stove or in the microwave.
Plate the dish by placing the cooked quinoa as the base, adding the roasted broccoli on the side, and topping with the grilled chicken breast.
Serve immediately and enjoy this balanced, flavorful meal.