Brush a rimmed baking sheet or large baking pan with 1 tablespoon oil.
Halve any large carrots. Chop into 2-inch pieces. Add carrots to the pan and drizzle with the remaining 2 tablespoons of oil. Sprinkle with salt and pepper and toss to coat. Spread carrots into an even layer.
Roast for 25 minutes, stirring halfway through, or until carrots are tender and starting to caramelize. If browning too quickly before softening, cover loosely with foil. Sprinkle with chopped herbs before serving.
Cutting the carrots diagonally increases the surface area so you can get even more caramelized parts on the carrots.
Make sure to heat the oven to 400F fully. If the temperature is not correct, you won’t get the delicious caramelization shown in the photos.
If you have a large sheet pan, use it! The more you’re able to spread the carrots out in a single layer, the more caramelization you’ll get. Divide into two sheet pans if your pans aren’t large enough.
Make sure to measure the olive oil. The olive oil helps the carrots caramelize but too much, and it’ll cause the carrots to be soggy.
For sweeter oven-roasted carrots, you can add a touch of honey or brown sugar.