Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Peel and dice the sweet potato into 1/2-inch cubes and place them on the baking sheet.
Toss the sweet potatoes with 0.5 tablespoon of olive oil, 0.125 teaspoon of sea salt, and 0.125 teaspoon of black pepper.
Roast the sweet potatoes for 15 minutes, then add the asparagus to the same sheet, tossing with a tiny bit of the remaining oil.
While vegetables roast, season the chicken breast on both sides with garlic powder, dried rosemary, and the remaining salt and pepper.
Heat the remaining 0.5 tablespoon of olive oil in a non-stick skillet over medium-high heat.
Place the chicken in the skillet and sear for 5 to 7 minutes per side until the exterior is golden-brown and the internal temperature reaches 165°F.
Remove the chicken from the heat and immediately drizzle with fresh lemon juice to deglaze the pan slightly and coat the meat.
Plate the crispy chicken alongside the roasted sweet potatoes and asparagus, drizzling any remaining pan juices over the top.