Howard and his team-mates were far too good for their lower division hosts and the only surprise was that it took them so long to wrap the game up.
In only the second minute the Hatters intentions were made clear when a brilliant 20-yard shot by Kevin Nicholls was equally well saved by Wycombe's Frank Talia.
The first goal came when Howard produced a magnificent finish from an Ahmet Brkovic cross from the right on twenty minutes.
Striker Nathan Tyson's burst past Curtis Davies and shot that was well saved by Marlon Beresford was Wycombe's only shot on target throughout.
The killer second goal arrived when Nicholls this time hit his shot past the outstretched dive of Talia after seventy minutes.
The third Luton goal came from another Brkovic cross which Howard headed powerfully past the overworked keeper.