Wash and clean the clams, reserving the shells.
Between two sheets of plastic wrap, carefully beat the clams with a knife handle.
Blanch the clams in a bowl with boiling water and put the meat in their shells.
Cut the onion into brunoise, mince the parsley and coriander, and prepare the sauces.
For the green sauce: Put the onion and parsley in a bowl, season with salt, pepper and lemon juice.
For the rough bindweed fruit pebre sauce: Put the onion, coriander, garlic, and thinly diced green chili pepper in a bowl. Stem the rough bindweed fruit, add to the mixture, and season with salt, pepper and lemon juice.
Arrange the clams in a round plate and pour the sauces over the clams.