Preheat the oven broiler on high.
Slice the French bread into 1/2-inch thick pieces.
Place the bread slices on a baking sheet and position the rack about 6 inches below the broiler element.
Broil the bread slices for about 1.5 minutes on each side or until they are golden brown and crispy. Keep a close eye on them to prevent burning.
In a bowl, scoop out the ripe avocado and mash it with a fork until smooth.
Add Greek yogurt, mayonnaise, and freshly squeezed lemon juice to the mashed avocado. Mix well to combine.
Season the mixture with salt and pepper to taste. Adjust the seasoning according to your preferences.
Once the crostini are ready, spread a generous amount of the avocado mixture onto each slice.
Carefully drape a slice of smoked salmon over the avocado spread on each crostini. You can fold the salmon to fit nicely on the bread.
Wash and chop the dill finely.
Sprinkle chopped dill over the smoked salmon for a burst of fresh flavor.