Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Wash and peel the sweet potato, then cut it into uniform 1-inch cubes.
In a small bowl, mince the garlic cloves and combine with the rosemary, thyme, sea salt, and black pepper.
Place the chicken breast on one side of the baking sheet and rub with 0.5 tbsp of olive oil and half of the garlic-herb mixture.
Toss the sweet potato cubes with the remaining 0.5 tbsp of olive oil and the rest of the herb mixture, then spread them in a single layer on the other side of the sheet.
Roast in the oven for 15 minutes.
While the chicken is roasting, trim the woody ends off the asparagus spears.
Remove the baking sheet from the oven, add the asparagus to the tray, and return to the oven for an additional 10-12 minutes.
Ensure the chicken has reached an internal temperature of 165°F and the vegetables are tender and slightly browned before serving.