Hydroponics
From Starsonata Wiki
Hydroponics is a tech level 0 base item that produces 1 Space Oat every 10 seconds. They can be found in DG galaxies starting at about Danger Factor 200 or by completing the Adonis, Argonaut or Ambrosia Radar missions.
With enough MRE factories (1), each hydroponics produces enough rations to supply 299 workers infinitely.