To make the trinchado sauce, heat the oil and butter in a large frying pan, and fry the onion, garlic and bay leaves for 5 minutes.
Add all the Hinds Spices and fry for another 2 minutes.
Pour in the red wine vinegar, beef stock, tomato paste and soya sauce and simmer gently for 30 minutes. Pour in the cream and add the zest of the lemon.
Heat a pan with oil and brown the rump cubes. Set aside, toss into the trinchado sauce and serve in rolls.