Prepare the Creamy Base: In a medium-sized mixing bowl, combine ½ cup of mayonnaise with 2 tablespoons of ketchup. Whisk or stir until the mixture is smooth, evenly blended, and turns its classic pink color.
Add Texture and Sweetness: Mix in 2 tablespoons of sweet pickle relish and 1 tablespoon of finely chopped onion. Stir well to distribute the crunch evenly.
Season and Acidify: Add 1 teaspoon of white vinegar (or lemon juice) for brightness, along with a pinch of salt and pepper. If using, add a dash of Worcestershire or hot sauce at this stage.
Fold in the Egg: Gently fold the finely grated hard-boiled egg into the mixture. This is the chef's secret to achieving the signature traditional texture and depth.
Chill and Set: Cover the bowl or transfer the mixture into an airtight mason jar. Refrigerate for at least 15 to 30 minutes before serving to allow all the vibrant flavors to meld together.