Bring a 4-qt. pot of water to a boil. Add onions and cook for 1 minute. Using a slotted spoon, transfer onions to a large bowl of ice water and let sit for 5 minutes. Drain onions and, using a small knife, remove skins; set aside.
Season the rabbit with salt and pepper. Heat oil in a 5-qt. Dutch oven over medium-high heat. Working in 3 batches, add the rabbit and cook, turning once, until browned, about 8 minutes. Transfer rabbit to a plate; set aside. Add onions and cook, stirring occasionally, until golden brown, about 5 minutes. Add tomatoes, broth, tomato paste, prunes, cloves, garlic, bay leaves, rosemary, and cinnamon. Nestle the rabbit in the pot, cover, and bring to a boil. Reduce heat to low and cook until rabbit is very tender, about 45 minutes.
Transfer rabbit to a large platter. Set a medium strainer over a 1-qt. saucepan. Strain the cooking liquid, discarding bay leaves and rosemary. Transfer the onions and prunes to the platter. Simmer the strained sauce over medium-high heat until slightly thickened, about 8 minutes. Skim excess fat from surface, season sauce with salt and pepper, and spoon over rabbit. Serve stew garnished with parsley.
