Halve <quantity>2</quantity> large oranges

Extract <quantity>200<unit>ml</unit></quantity> of fresh orange juice

Add the orange juice and <quantity>260<unit>g</unit></quantity> of sugar to a saucepan over medium heat

Mix it and cook for 5m until the sugar is completely dissolved. Stir occasionally to help with the process. The orange syrup is ready

Add <quantity>20<unit>ml</unit></quantity> of pineapple juice and <quantity>22.5<unit>ml</unit></quantity> of lime juice to a cocktail shaker

Add <quantity>22.5<unit>ml</unit></quantity> of the Orange Syrup and <quantity>2.5<unit>ml</unit></quantity> of orange blossom water

Add <quantity>2<unit>dashes</unit></quantity> of Peychaud's bitters and <quantity>60<unit>ml</unit></quantity> of white rum

Add ice cubes as needed and shake

Strain into a tumbler glass with ice

Garnish with a nasturtium leaf. The O2 is ready

Cheers!