This is a good example of a simple position that should be recognized instantly. It is easily calculable, but it should be a position that requires no calculation on your part. That's not to say that you won't confirm what you know if there's time available, but presume that you have virtually no time, and you can play a short series of forcing moves to arrive at this position. Do you play them? Does it matter who's to move in this position? Include such positions in your tactics drill set.
Suggested Reading in order of recommendation:
Silman's Complete Endgame Course--Jeremy Silman
100 Endgames You Must Know--Jesus de la Villa
Dvoretsky's Endgame Manual--Mark Dvoretsky (available in book and software)
The ABC of Endgames--ChessBase software