Brown lamb - Sprinkle lamb with salt and pepper. Heat the oil in a large heavy based pot over high heat. Brown 2 pieces of the lamb until deep golden on both sides, about 2 - 3 minutes per side. Remove into a bowl and repeat with the 3rd piece, adding more oil if needed, then remove.

Soffrito - Lower heat to medium, cool the pot a bit if it's very hot and scrape out any loose black bits. Add a bit of oil if needed. Then add the onion, celery, carrot, garlic and rosemary. Cook slowly for 7 - 8 minutes until softened but don't let them colour.

Deglaze and reduce wine - Turn heat up to high and add the tomato paste. Stir for 1 ½ minutes to cook out the sourness and deepen the colour from red to brown. Then add the wine and simmer rapidly, scraping the base of the pot, until reduced by half.

Slow cook - Add tomato, stock, 3 rosemary sprigs, bay leaves, crumbled stock cubes, salt and pepper. Mix, add lamb and let it come to a simmer. Then put the lid on and reduce the heat to low or medium low so it's simmering very gently. Slow cook for 2 hours or until the lamb is tender enough to shred.

Shred - Remove lamb and shred using two forks. Cut excessively long strands using scissors.

Reduce sauce - Remove and discard rosemary and bay leaves. Return lamb into sauce and add the remaining 2 rosemary sprigs. Toss, then simmer on medium low for 30 minutes with the lid off, stirring every now and then, until the sauce has reduced and is thickened.

Cook pasta - Bring a large pot of water to the boil with the salt. Add the pasta and cook per the packet directions minus 1 minute.

Reserve water - Just before draining, scoop out a mugful of the cloudy pasta water. Drain pasta.

Toss - Return pasta into the pasta cooking pot with 6 - 7 cups of the warm ragu. Set the pot over medium high heat. If your ragu was very thick rather than saucy, add ¼ to ⅓ cup pasta cooking water. Then toss with spatulas until the meat is tangled through the pasta.

Serve - Divide between warmed pasta bowls or pour into a large serving bowl and let everyone help themselves with parmesan on the side.