Mix flour, salt, and baking soda in a bowl.
Add egg yolk and soda water a bit at a time until you have the consistency of a thick pancake batter. Mix in the lobster and the scallions.
In a saucepot, heat 2 inches of canola oil to 350°F.
Carefully drop small spoonfuls of the fritter batter into the oil, being careful not to crowd the pan (7 or 8 at a time). Fry until golden brown flipping the fritters once or twice with a spoon.
Remove the fritters with a slotted spoon and drain them on paper towels. Season with salt.
Serve with tartar sauce or dressing of your choice.