I was intending to cook roast beef with a joint of sirloin, but unfortunately my wife has returned from the supermarket with the sirloin already cut into slices (it wasn't her fault, and I don't know why the butcher sliced the meat). My question is: would it still be possible to roast the sirloin as if it were one joint or should I try a different cooking method? 
It depends what the recipe is, but I've successfully replaced brandy with orange juice or apple juice in the past. It's not a direct replacement for the flavour, of course, but gives a similar strength of flavour, if you see what I mean. 