Preheat oven to 450. Lay the carrots in a roasting pan & toss with 3 tbls oil. Season with 1 1/2 tsp salt and a few grinds of pepper. Roast for 20 minutes. Turn the carrots, add the onion and roast 15 more minutes, until the carrots are brown and tender. When the carrots are cool enough, cut them in 1/4 inch dice. Warm 2 tbls oil in saucepan. Add the carrot & onion mixture, the chili and the cayenne pepper. Cook, stirring, for 1 minute. Stir in the lentils. Add the stock and simmer, stirring occasionally, for 20-25 minutes. Season with the rest of the salt and pepper to taste. Serve with rice, or as a thick soup/stew (ragout!).