Pre heat the oven to 150c.
In a large dutch oven, fry lamb over medium heat for 15-20 mins, browning all sides as best you can & remove lamb to a plate.
Carefully drain fat from the pot using paper/kitchen towel, and fry capsicum and onion over medium-high heat for 10-15 mins, or until the moisture from the veg has cooked away.
Add flour, mix over low heat for 30 seconds.
Add tomato paste, mix over low heat for 30 seconds.
Add wine, paprika & thyme, bring to the boil over high heat, making sure to scrape up all the flavoured spots from the bottom of the pot. Simmer until wine starts to reduce, about 1-2 mins.
Add stock and bring to boil over high heat, then add back lamb, fat side up. Drizzle some of the stock mixture over the top of the lamb.
Bake, covered for 3 ½ - 4 hours, you know it is done when the meat is soft and falls away from the bone.
Remove lamb from stock and shred, discarding bones and fat, then simmer stock over medium heat on stovetop (uncovered) for 20mins to thicken the sauce.
Add shredded lamb to sauce and serve topped with sour cream or smooth ricotta.