The phrase "an even more fascinating" is correct and usable in written English.
It can be used when comparing something that is already fascinating to another thing that is even more so.
Example: "The documentary on space was interesting, but the one about the ocean was an even more fascinating exploration of our planet's mysteries."
Alternatives: "even more intriguing" or "even more captivating".
This is an even more fascinating phenomenon: all things, as the new-agers like to say, have a natural cycle.
But if President Obama's nominee, Merrick Garland, is confirmed, the court would shift to an even more fascinating makeup: conservative Catholics and liberal Jews — though not entirely, as Justice Sonia Sotomayor, an Obama pick, is also Catholic.
The world got an even more fascinating glimpse of what he's got in there a few months later when, on the morning of the final day of reshoots, Gibson's bilious rants to his ex-girlfriend surfaced.
Earlier this month, researchers at the University of California at San Francisco and at the University of Toronto announced an even more fascinating way to use the fossils in our genome.
And not only that, one ended up investing in the other, making for an even more fascinating conversation.
If you already know the surprise, it'll make watching George and Martha's interactions throughout the play an even more fascinating experience.
With a film crew it was even more fascinating.
"Our new estimate of the younger age in a way makes this species even more fascinating because it has so many of these unique traits relative to other pupfish," says Christopher Martin, a biologist at the University of North Carolina, Chapel Hill, who led the study.
If you've ever attended a magic show and wondered how the person onstage performed a certain trick, it's even more fascinating to watch in disbelief when you're only seated five feet away from him.
Most people just see [the] Ethan app itself and are fascinated, but what's even more fascinating is that potentially everyone can be an Ethan".
Even more fascinating is a "wine cathedral" in nearby El Pinell de Brai.
