I guess it helps if you know its mate in 1... but white only has a couple checks that don't immediately drop the queen so it was pretty quick to narrow it down.
What is this pattern called: epaullatte, I think.
If you found this difficault I would set up a problem set with just these types of mates and do a couple hundred; probably wont be too hard.
The hardest mate-in-1 i've ever seen (not counting the promote-to-knight, castle and en passant puzzles): Tactic 91102