The Belgian striker netted a first half brace either side of Ross Barkley's goal to give the Toffees a 3-0 half-time lead.
Yohan Cabaye and Loic Remy struck in the second half to made it a more respectable scoreline, but it was the first half defensive horror show from the Toon which lost them the game.
Boss Alan Pardew struggled to explain some of the schoolboy defending, with full-backs Mathieu Debuchy and Davide Santon constantly caught out of position, and centre-backs Mapou Yanga-Mbiwa and Fabricio Coloccini beaten for pace.
"The first half, I'm afraid, wasn't good enough. The inconsistencies I spoke about before the game have come back to haunt us again," Pardew told nufcTV.
"We defended so much better in the second half. We didn't gift them any goals. They had to earn their chances and we caused them all sorts of problems.
"Hopefully our fans can go hope with something to hang on to - because after the first half I'm sure they just wanted to go home.
"Football is a simple game really. You have to tackle, you have to put your head in, you have to run forward, you have to pass forward and you have to show an ambition to win the game, which we didn't show in the first half - for whatever reason.
"The team was set up to try and win the game - but it looked like we made eleven changes at half-time. We're searching for the right balance in the team, not just us but every Premier League team".
Newcastle have now conceded six goals in their last two Premier League matches.
What do you make of Pardew's explanation? Which players need to be replaced for the Cardiff match?
image: © Brian Minkoff - London Pixels