In a large mixing bowl, combine the chopped lobster meat, Hellmann's mayonnaise, chopped tarragon, and chopped chives. Add salt to taste and mix well.

Cover the bowl and refrigerate the lobster salad until ready to use. You can make this up to a day in advance but I do it right when I'm making the sandwiches. The lobster salad should be cold when added to the buns.

Split the potato hamburger buns if they are not already split.

Place a generous amount of the cold lobster salad into each potato bun and sandwich with the other half.

Preheat a griddle or large skillet over medium heat. Add a generous amount of salted butter and let it melt.

Place the sandwiches on the preheated griddle.

Cook for about 1-2 minutes on each side, pressing down gently with a spatula, until the buns are golden brown and crispy on the outside. The lobster salad should remain cold inside. Remove the lobster rolls from the griddle. Serve immediately while the buns are hot and crispy on the outside and the lobster salad is cold on the inside.