Season the lamb generously with salt and black pepper.
Heat the olive oil in a large Dutch oven over medium-high heat.
Brown the lamb in batches for about 6 to 8 minutes, then transfer it to a plate.
Add the onion and celery to the pot and cook for about 5 minutes until softened.
Stir in the garlic and cook for 30 seconds.
Mix in the tomato paste and cook for 1 minute.
Return the lamb to the pot.
Add the diced tomatoes, beef broth, Worcestershire sauce, thyme, rosemary, smoked paprika, and bay leaves.
Bring to a boil, then reduce the heat to low, cover, and simmer for 1 hour.
Add the potatoes and carrots, then continue cooking for 30 minutes.
Stir in the green beans and simmer for another 15 to 20 minutes until the vegetables are tender and the lamb is fork-tender.
Remove the bay leaves.
Sprinkle with fresh parsley before serving.