I agree with kwired - it looks like all non-dwelling kitchens need GFCI receptacles.
Do the instructions for the stove allow hardwiring? When a contractor suggest hardwiring a cord and plug appliance, I always picture them cutting the end off the cord, and wire-nutting the SO cord into a box. Maybe they would do a better job than that, but I'm still not sure it complies with the stove's UL listing.
I'd have someone do a little more troubleshooting. Don and ptonsparky's suggestions should be investigated. Or maybe the stove is just bad. Maybe the GFCI circuit breaker is bad. (There is also a limit on the branch circuit length on GFCI breakers - maybe 100', maybe 200' - I can't remember exactly what the limit was.)
Try plugging it into a different standard gfci outlet and see if it still trips. Or try a different breaker. Or even try a standard outlet long enough to burn off any moisture like Don said.