Possible Clues:

• It's over oxygen and hydrogen, for example, produced by Palm raised in swamp
• Portuguese saint imports good grain for pudding
• Southeast Asia starch source
• Drop round for starchy cereal
• Staple food that may give South American energy
• Pudding made by son in the past
• It might make soup thicker if you turn up gas ring
• Powdered starch
• Pudding originally standard in the past
• Starchy pudding ingredient derived from palm stems