Cut Beef into four or five large pieces. Season with salt and pepper, and drizzle with a little olive oil. Heat a large frypan over a medium-high heat. Brown the pieces of Beef well on all sides. Remove and place in slow cooker bowl.
Reduce heat, add a little oil to the frypan and onion and garlic. Cook for 1–2 minutes, stirring occasionally. Add the flour and stir to scrape up residue from the base of the pan and ensure the onion is coated with the flour. Gradually pour in the stock and stir until the mixture boils. Pour over the Beef in slow cooker dish. Add the tomatoes and thyme and a small pinch of sugar.
Cover the slow cooker with its lid, cook on low setting for 6-8 hours and then 1 hour on high setting (if you have time). Alternatively, cook on the high setting for 4-5 hours. To serve, shred the Beef with two forks. Stir in the roasted capsicum and basil leaves. Serve over pasta and sprinkle with parmesan.