Season the rump all over with salt and pepper.
Heat the olive oil in a large saucepan over medium high heat. Once hot, add the roast to the pan and sear on all sides until browned. Remove from pan.
Add the sliced onions, and cook for a few minutes until softened. Add the garlic and the assorted bell peppers. Stir, and continue cooking for 2-3 minutes.
Add the oregano, cumin, paprika, black pepper, turmeric and salt. Stir to coat the vegetables in the spice mixture, and cook for 1 minute or so until spices turn fragrant.
Add the diced tomato, water, and soy sauce. Bring to a boil, then pour this into mixture into the slow cooker over the roast. Add the bay leaves , nestled among the mixture.
Cover slow cooker and cook on low heat for 8-10 hours or until beef is very tender and easily shredded. Stir in the olives and lime juice,