In a large bowl, mix the flour, coriander, cumin, paprika and rosemary seasoning to blend. Dredge the lamb chops in the seasoned flour to coat.
Heat the canola oil in a large Dutch oven over medium-high heat. Brown the lamb in the oil for 4 minutes. Then add the onions and cook until just beginning to soften, 2 minutes. Add the celery, peppers and half of the garlic. Saute for 5 minutes.
Add any remaining seasoned flour and cook for 1 minute--this will help thicken the stew. Stir in the tomato paste and canned tomatoes. Pour in the stock and season with salt and pepper.
Simmer for 2 hours, or until the meat is tender, stirring every 20 to 30 minutes and replenishing with water as needed. (Check the heat from time to maintain a gentle simmer.)
Add the carrots, potatoes and the rest of the garlic and cook for a further 20 minutes, until the vegetables are cooked but still firm.