Preheat the oven to 400 F
Slice the sweet potato into rounds, then in half. Toss them with half of the olive oil, the garlic powder, and salt & pepper
Bake for 15 minutes, remove from the oven and flip the potatoes.
Slice the asparagus into 2" pieces. Add them to the sheet-pan with the cooked potatoes and place the chicken between the veggies.
Drizzle the remaining olive oil and season with salt & pepper.
Whisk the marinade ingredients together until smooth, then pour the marinade over each chicken piece, reserving some to brush over after cooking.
Finish baking for another 35-40 minutes, until the chicken is cooked through.
Brush the remaining sauce over the chicken, and garnish with sesame seeds and scallions.