Cut the meat into 3cm cubes, getting rid of as much of the sinews and membranes as you can. In a bowl mix the meat well with the spices, garlic and the lemon and cover with clingfilm. Leave to marinate for several hours or overnight in the fridge, turning occasionally. Remove the garlic and sprinkle the meat lightly with salt.
In a large frying pan, heat the butter and oil until the but