Creating the Egg Salad Sandwich is easy if you follow these simple steps:

1. Boil the Eggs: Place the eggs in a saucepan and cover them with water. Bring the water to a boil over medium-high heat. Once boiling, cover the pan, remove it from heat, and let it sit for 10-12 minutes.
2. Cool the Eggs: After the eggs have finished cooking, transfer them to a bowl of ice water to cool for about 5 minutes. This makes peeling easier.
3. Peel the Eggs: Once cooled, peel the eggs and chop them into small pieces.
4. Mix Ingredients: In a large bowl, combine the chopped eggs, mayonnaise, Dijon mustard, salt, pepper, dill, celery, and red onion. Mix well until all ingredients are incorporated.
5. Taste and Adjust: Taste the egg salad and adjust seasoning as needed. You can add more salt, pepper, or mustard based on your preference.
6. Prepare the Bread: Toast the bread if desired. You can also use croissants or lettuce wraps for a different presentation.
7. Assemble the Sandwich: Spread a generous amount of egg salad on the bread and add lettuce leaves if using. Top with another slice of bread or close the croissant.
8. Slice and Serve: Cut the sandwich in half and serve immediately, or cover and refrigerate for later.

These steps will guide you in creating this incredible sandwich effortlessly.