Quickdraw - she BFRs him with a teleport or confuses him with her hallucinogenic dust, or he thunderclaps her, which would at least stun or knock her out.
I'm leaning more towards Ben being faster on the draw with the thunderclap, since the dust needs time to reach him, and she needs time to chant the teleportation spell.
The chant thing is weird, as we aren't totally sure if Pixie actually needs to.
Even under writers who usually have her chant, she doesn't always do it. Other times, she'll only chant one word. Sometimes, she'll teleport multiple times off one chant. I try and reconcile it by assuming she's gotten better with the magic. It's like she doesn't need to chant, but it might help focus.
It's kinda like when Scarlet Witch taught Pixie the Mists of Morpheus spell Doctor Strange uses. Sucked with it at first -- it's a sleeping spell but she made it a destructive energy blast that blew Rockslide apart. Later, she added her own twist onto the chant and put Crossbones to sleep.