Sparkling coffee with decaffeinated ice and chocolate shavings

Add a cup of decaffeinated coffee (I made it in the coffee maker) to a jar with a lid (I washed and reused the chickpea jar). Add ice to taste and the oat milk. Close the jar and shake vigorously until a layer of foam is formed.

Chop or grate the chocolate and add it on top of the foam together with the cinnamon.