Halve the avocados lengthways and stone them. Scoop out the pulp with a sharp-edged spoon and dice finely. Peel the eggs and also finely dice them. Finely chop the shallot.
Cut the smoked salmon into fine strips and mix with the eggs, shallots and avocado meat. Salt and pepper.
Pour into the avocado halves, garnish with caviar and drizzle with lemon juice.