Queen vs bishop + a 7th rank pawn yet dont know how to win it


 engine says more than +6 but how to win ? 

Actually can it be won if black doesn't blunder?


How about:   

Start with Qb7 / Kg2 / Kh3 then bring the King in to support a Queen mate? If necessary, you can allow the Pawn to Queen on the last move before mate.


The idea is to bring the queen to assist in covering the a1-h8 diagonal while allowing the White king to run via either Kh3 or Kf1. We make use of the fact that the bishop is unable to control the light squares to move our king along the light squares.


Just make sure not to interpose the queen with the king by accident.