This position comes from an unplayed variation in the game previously referenced in "Pawn Wars". In the actual game, my opponent played 34...h5. Had he played 34...a5 or 34...c5, my position still would have been winning, but I would have needed to find a move I had not worked out when I exchanged the rooks several moves earlier.
In this position, after 34...c5, White has only one move that maintains the win. Black is able to force White to find several such only moves. It is thus a good position with which to practice calculation skills. I routinely replay such positions against the computer. In one that I played out yesterday, I chose a seemingly risky line in which both players promoted pawns. Then, I missed the forced exchange of queens, winning by a more clumsy route.
White to move
Both players seek to run the other out of pawn moves. Whoever is forced to move his king will lose.