Henry de Bromhead's classy 11-year-old has now won all his four starts this winter after disposing of the gallant Foildubh.
Andrew Lynch made all the running on the 1-8 shot and only Foildubh could keep tabs on him, flattering briefly but being put in his place from the second-last fence.
Sizing Europe gave his supporters little cause for concern at a course where he had already recorded six of his 18 career wins.
Lynch did not have to get too serious, although Foildubh at least gave him a race as the pair were always well clear of the other three runners.
The dual Cheltenham Festival winner asserted in the closing stages to score by 10 lengths.
De Bromhead said: "It was a bit of a slog and he did what he had to do.
"He just looked very idle on ground that he wouldn't be mad about and his jumping was okay."
Sizing Europe holds three entries at Cheltenham in March, the Queen Mother Champion Chase, Ryanair Chase and Betfred Gold Cup, and De Bromhead said: "It hasn't really made any difference to where we'll go at Cheltenham – I'd say the Gold Cup is the outsider of the three options and we'll just see how everything unfolds.
"His most impressive win this year was probably the two-mile-four Clonmel Oil Chase."
Lynch said: "It's hard to go out and make the running on that ground.
"It's horrible tacky ground. He was just popping away, but he's done it well enough.
"I had a quick look going to the second-last and I knew Paul (Carberry, on Foildubh) was there, but once I got hold of my lad he picked up and went away. He's done it well.
"He was out on his own and when I did give him a kick he came up which was nice."