Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.
Peel the sweet potato and cut it into 1/2-inch cubes.
Toss the sweet potato cubes with half of the olive oil, a pinch of salt, and pepper, then spread them in a single layer on the baking sheet.
Roast the sweet potatoes for 20-25 minutes, tossing halfway through, until they are tender and slightly caramelized.
Season the chicken breast evenly on both sides with garlic powder, smoked paprika, salt, and pepper.
Heat the remaining olive oil in a grill pan or cast-iron skillet over medium-high heat.
Grill the chicken for about 6-7 minutes per side, or until the internal temperature reaches 165°F (74°C).
While the chicken rests, place the broccoli florets in a steamer basket over boiling water and steam for 4-5 minutes until bright green and tender-crisp.
Serve the grilled chicken alongside the roasted sweet potatoes and steamed broccoli for a balanced, clean-eating lunch.