Figure[White to move]

There is nothing new here except the use of the pin. First figure out where the offensive action is for White. You might try looking piece by piece. His rook attacks Black’s bishop; his bishop attacks Black’s knight; and his queen attacks the pawn on d6—which has two Black pieces behind it. When you see a line arranged like the d-file here, take notice and consider pinning possibilities. It’s not just the queen bearing down on the Black pieces and pawn that is of interest; it’s also the bishop attacking the knight on d7. Taken together these resources suggest possibilities for play on that file; and one way to play on a file is to pin something in the front to something in the rear.

So experiment with exchanges you can force. White can initiate 1. BxN, RxB. Now White pins Black’s pawn on d6 to the rook behind it. This is a classic case where a preliminary exchange by White creates a loose piece, drawing the rook forward and away from its guard—and thus also creating a pinned pawn in front of it. And the pin of the pawn means...? It means the bishop on c5 can be taken with White's rook.

A comparable way to see the idea is to note the lineup of Black material on the d-file and ask whether White’s queen has a pin because of it. The answer is no; but why? Because the knight behind the d-pawn is protected. One way to loosen such a piece is to take it and cause it to be replaced by a piece that then is loose; White uses that method here with BxN.