As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SMOKE APPEARED IN THE AFT GALLEY DURING TAXI OUT. THE AIRCRAFT WAS RETURNED TO THE GATE WITHOUT INCIDENT. MAINTENANCE FOUND THE NR 1 AFT GALLEY OVEN FAN FROZEN AND OVERHEATED. THE NR 1 AFT GALLEY OVEN WAS REMOVED AND REPLACED, OPERATION OF THE OVEN CHECKED GOOD. ALL AFT GALLEY OVENS WERE OPERATED WITH NO DISCREPANCIES NOTED.