Late goals from Emond Protain and Bilal Butt saw Cockfosters move into the third round of the London Senior Cup after recording victory at Barkingside.
The visitors controlled the majority of the opening period with Adem Ali bringing a smart save from the home keeper.
Bryan Mooney also came close as Cockfosters dominated the majority of the half with Barkingside restricted to long hopeful passes forward.
In the second period the Fosters continued to be frustrated but 19 minutes before full time the deadlock was broken.
Good build up work from Ali and Protain saw the latter find space to fire home.
The hosts didn’t look like getting into the game after going behind and Cockfosters sealed the win in the final minute as a flowing move saw Butt finish well.
The win sees Cockfosters travel to Corinthian Casuals in the next round.
On Saturday, the Reds eased into the second round proper of the FA Vase after securing a 3-0 away victory against Clapton.
The visitors started strongly and went ahead in the 19th minute as Butt put Alan Bolger through on goal and he coolly lifted the ball over the onrushing keeper.
Cockfosters continued to control the contest and nearly doubled their lead before the interval as Conor Staples saw a shot pushed onto the crossbar.
After the restart, Fosters did find the second goal as Butt found space in the area to convert Jack Cooks’ cross.
The scoring was rounded off with 15 minutes remaining as Butt fired home to see the Reds into the second round.