Greg Stewart struck twice, with Reece Brown, Daniel Cleary and Viv Solomon-Otabor all notching a goal apiece.
On what was a blustery afternoon, it was actually the visitors that made they better start.
But it was Blues that had the first attempts on goal.
Diego Fabbrini shot a yard wide, then the Brentford keeper pulled off a smart low save to deny Solomon-Otabor.
Brown, Charlie Cooper and Jack Storer all had further efforts before Blues deservedly took the lead after 36 minutes when Stewart’s shot squirmed under the goalkeeper and over the line.
At the other end, Connal Trueman was called into action on 43 to tip the ball round the post and maintain his side’s advantage.
With half-time rapidly approaching Brown doubled the score with an excellently taken solo effort.
The young midfielder collected the ball on the half-way line before running on with it, beating two players and drilling his shot home.
Blues continued with their positive attacking play after the break and were rewarded when Stewart fired home a peach of an effort from 25 yards to make it 3-0
But they weren’t done there. A snap shot from Storer was saved at the second time of asking by the Brentford keeper, before he prevented Solomon-Otabor from scoring close in.
But Solomon-Otabor wasn’t going to be denied for long as just minutes later he slid in to meet Dacres-Cogley’s cross and make it 4-0 to the hosts.
Stewart then came desperately close to claiming his hat-trick when his free-kick struck the apex of the post.
But he turned provider from the subsequent corner when he sent in a neat ball which Cleary powered home with his head to cap off a comprehensive attacking display from Blues.
: Trueman, Dacres-Cogley, Cleary (Maxwell, 85), Robinson, Wiggins, Solomon-Otabor (Lubala, 77), Stewart, Brown, Cooper (Baba, 77), Fabbrini, Storer (Popa 66).
Goals: Stewart (36, 54), Brown (44), Solomon-Otabor (50), Cleary (73).
Pictures by Roy Smiljanic.