Step 1

In a large bowl, toss the potatoes, carrots and/or parsnips with the rosemary, oregano, thyme, salt, pepper and olive oil.

Step 2

Tear off 4 foot-long pieces of heavy-duty foil or 4 2-foot-long pieces of regular aluminum foil and fold them over to create a double layer of insulation. Divide the vegetables evenly between the foil pieces, mounding them in the center of each piece. Crimp and seal the foil packets. Preheat a gas or charcoal grill for direct cooking over medium-high heat. Place the foil packets on the grill and cook for about 20 minutes, until the vegetables are tender and starting to caramelize in spots. (Take care when opening the foil packets, as steam will escape.) Serve immediately.