Possible Clues:

• Material available thanks to very loud Spanish terrorists
• Stuff with terribly fat cheese
• A shiny silklike fabric
• Welshman said thanks for material
• Evening-gown material
• With such fine stuff 'e got twice as fat
• Shiny silk with a crisp texture
• Wedding dress fabric
• Dressy fabric
• Taken aback at fine cheese, fine stuff indeed!