The other quest can be started by speaking to Lowe Meyer's Market. Once you do that head over to this location where you have to cook several dishes for the Chefosaurus. He is in a kitchen in the two of Sunbery.
You can get there via Securement Silo. Once you enter its a pretty straightforward path with elevators and distorted pathways. Once you beat the boss a gateway will open to Chefosaurus Rex deviant.