They beat Denham United 5-0 at Middlesex Stadium to set-up a trip to Charlton in the last four in February.
Charlton also play in the FA Women's Premier League South and the teams are currently level on points. The second semi-final is between KIKK, based out of Mile End and either Enfield or QPR.
Wendy Martin opened the scoring with a volley from Jenna Schillaci's corner and it stayed that way until half-time after Andra Marcoci was denied by the Denham goalkeeper.
The goals flowed in the second half as Wendy and Jenna combined to set-up Andra for 2-0, Wendy made it 3-0, Bianca Baptiste picked out Derrie O'Halloran for 4-0 and Bianca completed the 5-0 scoreline with a fine solo effort.
Juan Amoros, First Team Head Coach, commented: "We had a tough test coming away from home to play on a difficult surface and the girls did a superb job.
"The way we have been playing the last month has been brilliant and we continued this run with not just a great result, but a fantastic performance in every aspect of the game.
"We will give everything in the semi-final against Charlton to secure a place in the final."
The ladies are scheduled to take on Cardiff City back in FAWPL action at Ware FC on Sunday, 2pm.