4 large eggs
2 Tbsp mayonnaise
1/2 tsp prepared mustard of your choice
1/4 tsp kosher salt
2 tsp minced fresh flat-leaf parsley (optional)
Paprika or smoked paprika, for garnish (optional)
In a medium saucepan, place the eggs, and cover with water by one inch. Bring to a boil over high heat. As soon as the water boils, cover the pot and remove it from the heat. Let sit for 12 minutes. Then, drain the hot water, rinse the eggs under cold water, and shell the eggs. Set on a plate and place in the refrigerator for an hour or more.
Cut eggs in half lengthwise; gently remove the yolks and place them in a food processor or small bowl. (Tip: if the egg white halves are rolling around on your plate, slice a tiny bit off the outside of the bottoms, to make them sit up straight.) Add the mayonnaise, mustard, salt and parsley, if desired, to the yolks and process or mash together until smooth. Using a spatula, place the yolk mixture in a pastry bag fitted with a plain or fancy tip. Pipe the filling into the egg-white halves, swirling upward as you go.
Sprinkle eggs with paprika, if desired. Cover and refrigerate until ready to serve.