Place your eggs in a single layer in a saucepan and cover them with at least an inch of water. Bring the water to a rolling boil, then remove the pan from the heat, cover it with a lid, and let the eggs sit for about 10 to 12 minutes. Immediately transfer the eggs to a bowl filled with ice water to stop the cooking process and make them easier to peel.
Gently tap the eggs on a hard surface to crack the shells, then peel them carefully under cool running water. Use a sharp knife to slice each egg in half lengthwise. Gently remove the yolks and place them into a medium mixing bowl, setting the empty egg white halves aside on a serving platter.
In the bowl with the yolks, add the pitted and peeled avocado, mayonnaise, mustard, salt, and pepper. Use a fork or a potato masher to blend everything together until the mixture is completely smooth and there are no lumps of avocado left. For an even silkier texture, you can pulse the mixture in a small food processor for a few seconds.
Transfer the green yolk mixture into a piping bag fitted with a large star tip. Carefully pipe the filling into the hollows of the egg whites, swirling the bag upward to create a pointed shape that resembles a small evergreen tree. If you do not have a piping bag, you can use a plastic storage bag with a corner snipped off, though the star tip provides the best textured look.
Now comes the fun part. Place a tiny yellow pepper star at the very top of each green mound. Scatter the tiny red bell pepper squares across the sides of the filling to look like ornaments. Finish with a light dusting of smoked paprika and a sprinkle of fresh chives at the base to represent a festive holiday lawn.
