A much more optimistic Goodison Park witnessed their new manager Frank Lampard come out victorious in his first game in charge.
Yerry Mina got the scoring underway for Lampard’s reign as he headed the ball in from a corner in the first half.
Everton started the second half in some style as within three minutes they had doubled their lead through Richarlison.
Brentford pulled one back from the penalty spot but ten minutes later Mason Holgate made sure the game was to put to bed with a header.
Substitute Andros Townsend rounded off a very promising start for Lampard with a goal in injury time to make it 4-1 to the home side.
The first half started rather slowly with both sides struggling to work each other out.
It took until the 25th minute for an effort of any threat to be registered and it came from one of Everton’s inform players this season Anthony Gordon.
He cut in from the right and his effort in the end flew over David Raya’s bar rather harmlessly.
However just five minutes later Everton broke the deadlock as substitute Yerry Mina met Demarai Gray’s corner with force to head the ball into the net.
The first goal of the Frank Lampard era lifted Goodison Park as their team looked firmly in control of the cup tie for the rest of the first half.
Jordan Pickford was needed though five minutes before half-time as former Liverpool man Sergi Canos had a snapshot which needed tipping over.
Everton started the second half in quick fashion as Allan was found in a pocket of space in between Brentford’s midfield and defence.
Allan played a ball through to his fellow Brazilian Richarlison who clipped the ball over the onrushing Raya with ease.
Five minutes later in the 53rd minute The Bees found a route back into the game as Christian Norgard played a delightful ball to find Ivan Toney beating the offside trap.
Toney attempted to go round Pickford but the England goalkeeper impeded him which meant Michael Oliver pointed to the spot.
The striker stepped up with his short run-up and sent Pickford the wrong way.
It was game on for the away side.
Then ten minutes later it was game back off again.
Another corner from Demarai Gray inadvertently found Holgate’s head when he was just a few yards out and he was able to nod the ball in for his first goal of the season.
The game was all but done at that point, but Everton were still hungry for another goal and they got it in injury time.
Three substitutes all linked up as Cenk Tosun passed it to Alex Iwobi whose flick found Andros Townsend in the box.
Townsend hit the ball with power into the bottom right-hand corner as Everton scored four for the first time in a year since their manic 5-4 FA Cup tie against Tottenham last season.
It was a very promising start for Lampard as his side are now in the hat for the fifth-round draw.
A vital relegation six-pointer against Newcastle now awaits on Tuesday night.