Keep it simple: Make some prophylactical moves and then ... win!

Last week I played a training game in a chess club. So after winning a pawn in middlegame  we reached following position

It is an endgame with all heavy pieces on board. This is not so easy to play and to win. So how should I go on?

Put pressure on my opponent? Go on search for traps? Start with deep calculations? Look for kingside tactics? Or some other complicated stuff?

I decided to keep it simple and made some prophylactical moves. This stabilized my position and my adventage...and became the base for a winning attack