Place the eggs on a cutting board and cut a quarter off the egg from the fat rounded end to expose the yolk. Next, cut just a sliver off the opposite end, the pointed end so the egg is able to sit upright without rolling over. Once all the eggs have been cut, scoop out their yolks into a medium size mixing bowl. Place the egg white halves back into the egg container for easy transport and filling, making sure the holes are pointing up so that you are able to fill them with the Caesar mixture.
To the bowl with the yolks add the anchovy paste, Worcestershire, mayonnaise, garlic, onion, Parmigiano-Reggiano, lemon juice, salt and freshly ground black pepper. Mash up the yolks with a fork until the mixture is paste-like. Mix in half of the shredded romaine, reserving the rest for garnish.
Spoon the egg mixture into a plastic, re-sealable bag and squish it all into one of the bottom corners. Snip off the corner and squeeze out a bit of yolk mixture into each of the egg whites.
Once all eggs are filled, garnish them with a sprinkle of extra cheese and some additional shredded romaine. Close the container lid and you are off to that party!