How to Make It
Soften the gelatin in cold water in a heatproof bowl. Add the boiling water, sugar, and lemon juice and stir until the gelatin and sugar are dissolved. Cool.
Cut the eggs in half and remove yolks. Mash the egg yolks and mix with 1/3 of the gelatin mixture. Stir in the mayonnaise and pour into a lightly greased (with cooking spray) 6-cup mold. Chill until firm, 2 hours, then sprinkle with chopped parsley.
Chill remaining gelatin until thickened, 15 minutes. Chop the egg whites and add to thickened gelatin. Add the celery and olives and mix well. Pour over congealed layer in mold, and chill until firm, 2 hours.
Unmold onto a serving plate and garnish with hard-cooked egg slices and parsley sprigs.