The Tasty Trunk is a restaurant inside the trunk of a tree in Astoria. This is the hangout place for most people in Knight School. The restaurant is run by a Warlock.
In Opening Knight, the Phoenix Squad go to The Tasty Trunk to celebrate their new recruit, Arc. Prudence explains to Arc how The Tasty Trunk works. The Squad orders Vanilla Floats which are delivered by the Warlock, using Telekinesis. Sage and Buttercup come to Tasty Trunk to challenge the Phoenix Squad to take on the toughest quest.
After being kicked out of Phoenix Squad, Arc comes to sit alone in The Tasty Trunk. Sir Gareth comes over and orders club soda - which is soda in a large bowl, with actual clubs.