Preheat your oven to 400F and line a baking sheet with parchment paper.
If using whole carrots, quarter them or cut them into uniform sticks about 3-4 inches long and ½ inch thick. Try to keep them similar in size so they cook evenly.
Drizzle the carrots with oil, enough to lightly coat the carrots along with a teaspoon of kosher salt. Toss to combine and spread the carrots in a single layer on your prepared baking sheet. Roast for 15-20 minutes until they start to soften.
While the carrots are roasting, make your miso glaze. In a small bowl, whisk together miso paste, honey, soy sauce, minced garlic, and oil until smooth and combined.
Remove the carrots from the oven and drizzle about ¾ of the glaze over them. Toss the carrots until they're evenly coated.
Place the carrots back in the oven for another 10-12 minutes until they're slightly caramelized.
Remove from the oven and drizzle with the remaining glaze. Top with scallions and enjoy warm.