This quest can be acquired from Zora, the widow at Neuhof, after completing the main quest 'Ginger in a Pickle'. She will instruct you to ride her horse to Talmberg and participate in a race to prove to Sir Divish that Neuhof steeds are still the best in the realm.
You can now ride the horse to the Talmberg stables. Upon arrival, speak with Sir Divish and persuade him to see things your way. You can then speak with the stablemaster who will inform you that the race will be held the next day at noon (12:00). Attend the horse race and follow the markers on the map. They will loop back to Talmberg eventually, where the race ends. It is best to ride in a straight line toward each marker, avoiding the winding roads that the other riders will be stuck to. Once you have won the race, speak with Sir Divish and then go back to Zora to inform her.