Possible Clues:

• A cold mixture of Brie and cranberries initially used in tart
• Harsh, as criticism
• Caustic
• Sour in taste or harsh in tone
• Astringent in tone
• Sharp, fragmented breccia
• Bitter outstanding resistance meeting writer
• Bitter, seeing highest honour refused by incredibly courageous leaders
• Bitter writer sitting beneath tree
• Sarcastic card, first from rude writer