Cover quail eggs with 2 inches of cold water. Bring to a rolling boil, remove from heat, cover and cook for 2 minutes. Drain and rinse immediately with cold water.
Once cool, peel the eggs. Using a sharp paring knife, pierce the shell and membrane being careful not to reach the egg. Peel off the shell and membrane of the egg. Continue with remaining eggs.
Carefully slide the eggs in half and separate the yolks from the whites. Place the yolks into a small mixing bowl. Use a fork to mash the yolks with the mayonnaise, lemon juice, dry mustard and salt. Try to make the mixture as smooth as you can. Fold in the dill or fresh herb of your choice.
Transfer the mixture to a piping bag with a small tip, squeeze equal amounts of filling into each egg white. Alternatively, you can spoon into a ziploc bag and snip off the end and use this to pipe the mixture into the whites. Serve.