Melt the dark chocolate in a bain-marie until you get a creamy sauce. Set aside and leave to cool. Blend the bananas with the Isola Bio Oat Original Drink, peanut butter, and ice and blend until creamy. Pour the melted chocolate all around the edge of the glass so that it drips inside, then pour in the smoothie.
Garnish with the remaining square of chocolate finely grated on the surface and serve with a straw, which you can use to mix the smoothie with the chocolate sauce. Serve immediately.
PREPARED WITH: Isola Bio Oat Original Drink