Dissolved blue spirulina powder with hot water, and mix with simple syrup.
Make cold foam next. Heavy cream and milk with some vanilla extract. Whip to your thickness liking.
Put blue spirulina mixture that you made into bottom of your cup. Add some ice. Add milk to 2/3rds the way full of your cup. Add shot of espresso (I used freddo delicato pod for this). Add cold foam on top.
Optional: you can add a few drops of the blue spirulina mixture on top of the cold foam and stir it around with a chopstick (or toothpick).
by Relative_Pizza6179