In a stew pot over medium heat, heat 1/2 tbsp olive oil until it shimmers. Add onion, cinnamon stick, bay leaves, and oregano, and saute 5-10 minutes, until onion is soft and translucent. Add garlic and saute 30 sec until fragrant. Transfer to a bowl.
Add remaining oil to pot and heat until shimmering. Add lamb and brown on all sides. Return onion mixture to pot. Squish the tomatoes between your fingers to crush them thoroughly. Add tomatoes and red wine to pot, and add just enough water or stock to cover the lamb.
Bring to a boil then reduce heat to a simmer. Cover and cook 2-3 hours. If the meat has bones, remove them and discard. Add orzo and simmer 10-15 minutes more, until orzo is tender. Season with salt and pepper and serve.