Preheat the oven to 425°F (220°C).
Cut any larger carrots in half lengthwise so they're roughly the same size. Spread on a baking sheet and toss with olive oil.
In a jar, shake together the maple syrup, Dijon mustard, orange juice, and orange zest. Season with salt.
Drizzle all but 2 tablespoons of the maple Dijon glaze over the carrots, shaking the baking sheet to coat evenly.
Roast for 15 minutes, then remove from the oven and shake the baking sheet to redistribute the glaze.
Return to the oven and roast for another 10 to 15 minutes, until tender and lightly caramelized.
Transfer to a serving plate, drizzle with the reserved glaze, garnish with fresh parsley, and serve warm.