In a food processor, pulse the onion and garlic until minced. Melt the butter in a medium saucepan. Add the onion and garlic and cook over moderate heat until softened, about 7 minutes. Add the cinnamon, ginger and cayenne and cook, stirring, for 2 minutes. Stir in the tomato sauce and honey and simmer over low heat until the sauce thickens slightly, about 5 minutes. Season with salt and pepper.
Season the lamb chops with salt and pepper. In a large skillet, heat 2 tablespoons of the olive oil until shimmering. Add 4 of the lamb chops and cook over moderate heat, turning once, until browned and almost cooked through, about 8 minutes; keep warm. Repeat with the remaining 2 tablespoons of olive oil and 4 lamb chops.
Pour off the fat from the skillet. Add the tomato sauce and bring to a simmer over moderate heat. Add the lamb chops and simmer until cooked through, about 2 minutes. Transfer the lamb to plates, spoon the tomato sauce on top and garnish with the cilantro.