Possible Clues:

• Sports organisers take top off Armagnac after milk pudding
• Pak choi is plant regularly cut up for root starch
• I act OAP (anag) — edible substance made from cassava
• Draw liquid from one South American plant - it's starchy
• Dessert Calvin doesn't like in 'Calvin and Hobbes'
• Thanks, nothing is put in the picture with a starchy food
• Make apricot crumble without recipe and add a thickening agent
• Kind of pudding or starch
• Olympic officials, having tucked into Spanish food, almost finished pudding
• Volunteers to take in a film: about three-quarters through plot, it thickens