Heat oil in an 8-quart Dutch oven
or other large pot over high heat until hot but not smoking. Season meat lightly with salt and pepper and sear
in oil until browned on all sides, about 5 minutes. Add onions
and garlic and cook an additional 5 minutes. Add tomato paste and stir to incorporate, cooking for 2 to 3 minutes. Add celery
, carrots, parsnips, chick peas, wine, chicken broth, tomato sauce
, orange zest, segments and juice, and cumin
. Bring to a boil, then reduce heat, cover and simmer
until lamb is tender, about 90 minutes. Season with salt and pepper to taste. Remove from heat, cool slightly, and ladle into bowls. Top with fresh mint and serve.