Preheat the oven to 200 degrees Celsius/ 400 degrees Fahrenheit.
Peel the carrots or scrub them very well if they are organic and the peel looks fine. Make sure to dry them well with kitchen paper.
Place the carrots in a roasting tin that is large enough to hold all the carrots in one single layer.
Pour the olive oil on top and rub the carrots well until they are all coated in oil and spices if using (see blog post for suggestions). Sprinkle with salt and pepper.
Cover the dish tightly with foil. Roast the carrots for 10 minutes.
Remove the foil, shake the pan and continue roasting the carrots for 10 minutes more. Turn the carrots in the pan or shake the pan again and continue roasting the carrots until done to your liking, about 6-7 extra minutes in my case.
The cooking time will greatly depend on the size of the carrots, your oven, and your personal taste. I like crunchier roasted carrots and I find that rather thin whole carrots are done to my liking after this period of cooking time without foil, but you can cook them for a longer time if you prefer them to be softer.
Sprinkle with parsley and serve hot as suggested above.
The carrots should be medium and rather long and thin.