Place eggs in a pot of water and place over high heat. Once the water begins to boil, turn the heat down to medium-high and continue to boil for about 6-8 minutes. Remove from the eggs from the water and place into a separate bowl with cold water to help the eggs cool down. Peel the shells off and slice the eggs in half, lengthwise.
Remove the cooked yolk from the eggs, place into a medium-sized bowl and mix together with a spoon. Chop up all of the cooked egg whites and set aside. In the bowl with the cooked egg yolks, add in the celery, green onions, 1 tablespoon of mayonnaise, the Dijon mustard and the salt and pepper. Mix well, taste and adjust any seasonings as needed.
Add the cooked chopped egg whites to the mixture and the remaining tablespoon of mayonnaise. Mix together well and set aside.
Using a large non-stick pan over medium-high heat, heat the olive oil for a minute or two. Add the baguette slices and heat for a few minutes on each side or until nicely browned on both sides. Remove from the pan and place onto your serving platter.
To assemble the crostini: place about a tablespoon of the deviled egg mixture onto each toasted baguette slice and top with the pickled red onions and more diced green onions. Enjoy!