This is one of the three optional side quests available while Missing Airliner is active. Note that this mission will expire once Chapter 2 is started.

Client: Gwen
Pay: 800 Mira, 3 BP, Liberl Omelet Recipe
Bonus: None
Difficulty: Low
Locations: Anterose Restaurant
Description:

I'm in a bind right now, as I seem to be lacking a certain cooking ingredient I regularly use for practice.

Please bring Tender Poultry x5 to me, Gwen, at the Anterose Restaurant.

1. Gave Gwen the Tender Poultry!

If you don't already have enough Tender Poultry from fighting Mars Sparrows in the Prologue, head to Eisen Road and fight a few bird-class enemies there to get five of them, then talk to Gwen. To thank you, she will teach you how to make her Liberl Omelet, then just head back to the guild and report in for the rest of your reward.