Preheat your oven to 425°F (220°C) and adjust your oven rack to the middle position.
Trim the ends of the Brussels sprouts and cut them in half. Toss them in a bowl with olive oil, salt, and black pepper.
Spread the Brussels sprouts onto a baking sheet in a single layer. Roast in the preheated oven for about 20-25 minutes until they are crispy on the outside and tender inside, stirring halfway through.
While the Brussels sprouts are roasting, prepare the chicken breast. Pat it dry, season with salt and pepper, and lightly coat with a small brush of olive oil.
Grill or pan-sear the chicken breast over medium-high heat for about 5-6 minutes per side, or until thoroughly cooked and juices run clear. Let the chicken rest for a few minutes, then slice into strips.
In a small saucepan over low heat, combine honey, balsamic vinegar, and minced garlic. Stir well and let it simmer for 2-3 minutes until the glaze slightly thickens.
Once the Brussels sprouts are done, transfer them to a serving dish. Drizzle the warm honey-balsamic glaze evenly over the roasted sprouts and toss gently to coat.
Top the glazed Brussels sprouts with the sliced grilled chicken. Serve immediately and enjoy your balanced, protein-rich meal.