Possible Clues:

• Triple-decker lunch, or what can be found in 18-, 25-, 41-, and 52-Across
• Port served after all mem-bers had hefty snack
• Triple-decker lunch
• Order served with toothpicks ... and what each of the other four longest answers is?
• Deli order
• Diner order
• Three-layer snack
• Double-decker taking priest to Channel port
• Diner offering, perhaps
• Two places to go for golf and an extra large snack