Preheat your oven to 425°F.
Pat the chicken breast dry, then season both sides generously with the mixed herbs, salt, and pepper.
Place the chicken breast on a lightly greased baking sheet.
Trim and halve the Brussels sprouts. In a bowl, toss them with the olive oil, a pinch of salt, and pepper.
Spread the Brussels sprouts around the chicken on the baking sheet.
Wash the sweet potato and pierce it several times with a fork. You can either bake it whole on a separate tray or slice it into rounds for quicker roasting.
Place the sweet potato (or slices) in the oven alongside the chicken and Brussels sprouts.
Roast for about 20-25 minutes, or until the chicken is cooked through (internal temperature reaches 165°F) and the vegetables are tender with lightly crispy edges.
Remove from the oven, let the chicken rest for a few minutes, then serve together on a plate.