Grease bottom & sides of an 8" springform pan. In a bowl, combine eggs and mayonnaise until well blended. Spread mixture evenly on bottom of pan Sprinkle with chopped onions. Combine the cream cheese and sour cream until smooth. Layer the mixture onto the onion layer with a wet table knife or spatula, spread until smooth. Chill for at least 3 hours.

Top with a layer of caviar. Run a knife around the edges to loosen and lift out of pan. Arrange lomon wedges on top and decorate. Makes 10-12 servings.