I believe it is Qh3. Posting as a puzzle for those interested in finding the second move (not that hard really).
I have also included a number of variations, though not every one, so I may have missed a saving move but I think this does it. I also probably didn't include the "hardest" variation as the main line. I guess that depends on how you think 
I think this is one of those situations where it's a poorly designed puzzle: sure, you can spend a lot of brain power figuring out checkmate in two, but really, most moves are winning here - it's way easier to just win the rook or even sacrifice queen + rook for the rook, and White is still up by more than enough to force the win.
I think this is the sort of thing that helps distinguish between computer play and human play.
The puzzle reminds me of one from the Polgar 5334 book. I think they are more for calculation practice, with some patterns included, than just finding wins.
I think this is one of those situations where it's a poorly designed puzzle
Could you give us an example of a well-designed mate in two problem?
If you want Danny Rensch's 60 Tactics Trainer puzzles in 60 minutes or whatever the number is, there'll be quite a few
That doesn't help. None of his puzzles are labelled to indicate which are well designed and which are poorly designed according to Caedrel.
@Caedrel You may be confusing the art of chess problems with practical play, and they are two different things. The beauty of a composed mate-in-two is that there is only one key move, hard to find, which forces mate on the very next move: the fact that it is invariably a trivially won position is not the point. "Tactics trainer" puzzles, on the other hand, are geared towards practical play and feature positions where the outcome of the game is still in the balance and the task is to find a specific sequence which puts the result of the game in no doubt.
How did I miss the Rxf2 line? That was one I should have included. 
White has to checkmate in 2 moves.