You gotta try dog conch
It's especially common throughout Krabi Province, and considered to be a local delicacy.
Most Thais make a point of eating hoi chak teen when they're here, as it's considered to be a highlight of the local cuisine.
You need to keep an eye on the beach. The locals know the right time to forage each type of shellfish, and this one is on an outgoing spring tide, at a certain water level.
It's fun to join the hunt. Krabi people suddenly emerge from their houses 'en masse' and converge on the beach like some weird sort of foraging 'flash mob'.
Being algae-scoffing sand-dwellers, they're usually quite dirty when you get live ones. The locals in Krabi 'choke' the shellfish in a bucket of seawater or fresh water with salt and a few crushed Thai chillies.The poor molluscs prefer non-spicy water, so they end up sputtering around and pushing the sand out with their foot in a disgruntled fashion. This takes about 40 minutes to an hour.
They are called “Hoi chak teen” in Thai. ‘Chak teen’ means ‘feet pulling’ and hoi means ‘shell’. The obedient wee dog conch lives up to it's name and pulls it's foot around trying to get out of the spicy chilli water.
Treat these differently from normal shellfish. i.e. Don't boil the water first.
Start them in cold water and heat gently.
This way, the dog conch wave their foot, so when cooked it's sticking out a little bit and you can easily get them out of the armour. Easy that is, if you have the right tools.
Just grill for a few minutes, and remember to not overcook dog conch as they'll get tough, dry and leathery
Pull them out of their shell after a quick blanch in boiling water, and use them in curry, a soup, or a tasty Thai salad.