Preheat oven to 425 degrees fahrenheit.  Peel carrots and trim stems. Cut each carrot in half lengthwise.  Place on a large baking sheet and toss with olive oil. Roast for 25 minutes, stirring once. 

While carrots are cooking, melt butter in a small saucepan.  Stir in lime juice, chipotle pepper and garlic, then stir in prunes.  Pour over carrots and toss well to coat. 

Return to oven and cook for 2 to 3 minutes more or until very hot.  Sprinkle with cilantro.  Makes 4 to 6 servings.