Prepare the vegetables. You may peel or not peel. Cut all the vegetables to a similar size so they cook at an even rate, thus not getting some over-cooked, while others are raw.
Herb Oil
Remove the leaves from the thyme and rosemary, then loosely chop.
Combine the thyme, rosemary, garlic, and oil in a small bowl.
To Cook
Place the prepared vegetables in a Dutch oven then tip the herb oil over the top. Gently toss the vegetables so they are completely covered in the oil and herbs.
Bring the Dutch oven to a temperature of about 350 degrees F (180 degrees C), then cook for about 1 hour, turn the vegetables once during this time.