Hard-Boil the Eggs:

1. Cook the Eggs: Place the eggs in a saucepan and cover them with cold water. Bring to a boil over medium-high heat.
2. Simmer and Cool: Once the water reaches a rolling boil, turn off the heat, cover the saucepan, and let the eggs sit for 10-12 minutes.
3. Cool the Eggs: Transfer the eggs to an ice bath and let them cool for at least 5 minutes. This step makes peeling easier.

Peel and Halve the Eggs:

4. Peel the Eggs: Gently tap the eggs on a hard surface to crack the shells, then peel them under running water.
5. Slice in Half: Cut each egg in half lengthwise and carefully remove the yolks, placing the yolks in a mixing bowl.

Make the Filling:

6. Mash the Yolks: Mash the egg yolks with a fork until they’re crumbly and fine.
7. Mix the Filling: Add mayonnaise, mustard, vinegar or lemon juice, sugar, salt, and black pepper. Stir until smooth and creamy.

Assemble the Deviled Eggs:

8. Fill the Egg Whites: Spoon or pipe the filling into the egg white halves. Using a piping bag with a star tip creates a professional look.
9. Garnish: Sprinkle paprika over the eggs and garnish with fresh chives or parsley, if desired.

Serve and Enjoy: Chill the eggs in the refrigerator for 15-20 minutes before serving to allow the flavors to meld together.