Lamp shell (Lingula anatina) are known to the Vietnamese by other names like cà xỉu (South Vietnam), đuôi heo (Central Vietnam), or giá biển (North Vietnam). In Hà Tiên city (Kiên Giang province), lamp shell is a delicacy, especially the fermented lamp shell, which can be eaten with rice, or making salads. Fermented lamp shell is often the “tails” of lamp shells fermented with fish sauce.
Green papaya salad with fermented lamp shell (Vietnamese: gỏi đu đủ cà xỉu) is one common way to enjoy the fermented lingula shells. The main ingredients are green papaya strips, and fermented cà xỉu, but it can made in to a better dish by adding more ingredients like morning glory strips, “điên điển” flower (Sesbania bispinosa), asparagus beans,….
Prepare a big bowl of cold water with some ice cubes. Peel the papaya, then cut into fine julienne strips. Submerge the papaya in cold water for 4 minutes, then drain. (Or you can keep the strips in the fridge.)
In a large bowl, add the papaya strips, morning glory ribbons, tomato wedges, "điên điển" sebania flowers, asparagus beans. Pour the fermented lamp shells (including the water) into the bowl, add some "mắm ruốc" fermented krill paste (optionally), and squeeze some lime juice, then mix up all the ingredients.
Turn the salad out onto each serving platter. Garnish with the Vietnamese mint leaves, coriander leaves, peanuts, and eggplant slices. The salad dish isoften served with some prawn crackers.
"Mắm ruốc" krill shrimp paste is optional if you don't like its strong smell.
You can poach asparagus beans, instead of soaking in salty water.
Add some chili slices for more hot/pungent taste.