Soak the lentils in enough water to cover and set aside.
Meanwhile, in a crockpot turned to the high setting, combine the oil, onion, garlic, carrots and celery. Add 1/2 tsp salt and half of the ground black pepper. Give it all a good stir, cover with the lid, and walk away from it for 30 minutes. (You can make this dish fat-free by adding a couple of tablespoons of stock instead of the oil). I find this first extra step of "sweating" the mirepoix of onions, carrots and celery really helps build the flavor.
After 30 minutes, take off the lid, give everything a good stir, and add the lentils, tomatoes, vegetable stock, dry herbs, chipotle chili, remaining black pepper and salt to taste.
Mix well and cover the crockpot again. Let the bolognese sauce cook for two hours on the high setting or until the lentils are tender. The carrots will still have some bite, which is wonderful. Check salt and add more if needed.
Cook the pasta according to package directions. Add to the crockpot and give everything a good stir. Add some of the pasta cooking liquid if the pasta is too dry.
Garnish with fresh parsley and serve hot.