In a cocktail shaker, combine lemon juice, lime juice, egg white, gin, sugar cubes and orange blossom water. Dry shake for 30 to 45 seconds. Add crushed ice and cream to the mixture and shake again until pebble ice is dissolved. Shake one last time with 1 large piece of ice and strain into a fizz glass. Top with soda to the brim and wait a few seconds for the fizz to subside. Top again until the drink rises up over the rim of the glass, and serve.