Method

• 1.
  Place orange in a saucepan and cover with cold water, placing a small heatproof saucer over orange to keep it submerged. Bring to the boil over medium heat and cook for 1 hour 30 minutes or until very soft.

• 2.
  Cool completely, then transfer to a blender and whiz until smooth. Pass through a fine sieve into a bowl. Line glasses with orange puree.
• 3.
  Fill blender with ice, add Aperol and blend until smooth and slushie-like. Spoon into glasses. Top with prosecco and soda, and garnish with bay leaves to serve.