In a Dutch oven, add 2 inches of water; bring to a rolling boil. Add lobsters, cover, and steam for 8 minutes. Remove lobsters, reserving liquid. When cool enough to handle, remove meat from claws and tail, reserving any juices; refrigerate meat and juices. , In the same Dutch oven, cook carrots and onion in butter over medium-high heat until tender, 5-8 minutes. Stir in tomato paste and cook until it starts to caramelize, about 5 minutes. Add garlic; cook 1 minute. Stir in wine and simmer until reduced by half. Add lobster shells, bodies, reserved cooking liquid, reserved lobster juices and stock. Bring mixture to a simmer; cook 1 hour. Strain mixture, pressing to extract as much liquid as possible; discard shells and solids. , Return liquid to Dutch oven. Add rice and cook until extremely soft, 25-30 minutes. Puree in a blender until smooth. Add cream, thyme, salt and pepper. Bring mixture to very low simmer; add reserved lobster meat and cook until heated through. If desired, sprinkle with additional black pepper and parsley.