Place the 6 large eggs in a single layer in a saucepan or pot. Fill with cold water to cover the eggs by about an inch. Bring the water to a rolling boil over medium-high heat. Once boiling, cover the pot with a lid, turn off the heat, and let the eggs sit for 10-12 minutes.
Drain the hot water and immediately transfer the eggs to a bowl of ice water to cool for at least 5 minutes. Gently crack the shells all over and peel under running water if needed. Pat the eggs dry with a paper towel.
Slice each peeled egg in half lengthwise. Carefully remove the yolks and place them in a medium mixing bowl. Set the egg whites aside on a serving platter.
Add mayonnaise, Dijon mustard, chopped pickled banana peppers, apple cider vinegar, salt, and pepper to the bowl with the yolks. Mash everything together with a fork or use a hand mixer until smooth and creamy. Taste and adjust seasoning if necessary.
Spoon the yolk mixture back into the egg white halves. For a neater presentation, you can use a piping bag or a resealable plastic bag with the corner cut off to pipe the filling neatly.
Sprinkle the deviled eggs with freshly chopped parsley for a burst of color and freshness. If using, add crumbled cooked turkey bacon on top for extra texture and smoky flavor. Serve chilled or at room temperature.