Head to the castle kitchen to find Katherine. If she isn't there, the local cook can help you secure the wine Sir Hans requested.
KCD2's combat rewards patience. Use your master strikes and watch your stamina; getting winded during this quest is a recipe for a "Game Over" screen. for_victory
While the quest says "this evening," you aren't strictly on a 24-hour timer. You can delay for a day or two to get your affairs in order. 3. The Quest Objectives: Wine, Armour, and Stealth Head to the castle kitchen to find Katherine