A Trellan crepe was a type of food.
In 2372, Tuvix, a lifeform created during a transporter accident in which Neelix and Lieutenant Tuvok were merged, noted that Trellan crepes were Kes's favorite food and Neelix always served them on a Wednesday. He later cooked some for her, altering the recipe slightly by adding spices to allow the flavor of the mushrooms to come through. Kes thought they were "absolutely delicious." (VOY: "Tuvix")