As soon as you purchase clams, de-grit them to purge sand (Read on How to De-Grit Clams). It takes about 1 hour to do this process.
Start the grill. Meanwhile, prepare the rest of the ingredients. Chop green onions, cut butter into small cubes, and combine the seasonings in a small bowl.
When the grill is hot, place the clams on it. When the clams are fully opened, after about 5 minutes, pour the Seasonings and put green onion and butter on the clams, and cook until boiling. Carefully remove them from the grill. Try not to spill their juices.
Serve on top of the sea salt. Enjoy!
To Store
I don't recommend keeping the clams for a long time, so enjoy it on the same day you cook.