Cut the carrots into 1" pieces. Toss them in a bowl with the olive oil, maple syrup, dijon mustard, parsley, garlic powder, salt, and black pepper. Mix well until they're all coated.
Transfer them to a parchment-lined sheet pan. Pour any remaining marinade over the carrots.
Roast for 45-50 minutes, flipping halfway through.
Garnish with extra parsley when ready to serve and a pinch of salt if needed.