Simone Zaza also found the target as Slaven Bilic had plenty to be optimistic about after seeing Aaron Cresswell successfully come through his first game after suffering a knee ligament injury during the Club's pre-season tour to Austria.
Cresswell played 50 minutes and will now be hoping to be in contention for the Premier League game against Crystal Palace on 15 October.
Dimitri Payet might have stolen all the headlines against Middlesbrough with his wonder goal but Lanzini showed he can also steal the show with another impressive display following his recent return to first-team action.
The 23-year-old played a part in all three goals and turned provider for the first when he played a perfect through ball into the path of Zaza.
The Italian forward, on-loan from Juventus, showed his quality in front of goal when he fired an impressive finish past Raphael Spiegel.
Lanzini doubled the lead when he showed a great piece of skill to burst clear into the box and struck the ball into the corner of the net.
The talented midfielder made it three late in the game when he was picked out by Club skipper Mark Noble and fired a superb finish past Spiegel.
Bilic was keen for his for his players to keep up their match fitness over the international break and also saw Adrian, Alvaro Arbeloa and Pedro Obiang compete in a strong starting line-up.
West Ham TV caught all the action and were on hand to see our Argentine midfielder back to his best.