Clean the rhubarb and cut into coarse pieces. Bring the water and 30 grams of sugar to the boil. Add the rhubarb pieces and simmer gently for about 5 minutes. Take the pot off the stove and let it cool down.

Beat the cream until stiff. Mix the water, cocoa powder and 50 grams of sugar in a small saucepan and simmer for about 5 minutes. Coarsely break up the meringue drops and put 3 aside for the decoration. Layer alternately rhubarb, broken meringue and cream in 3 glasses Drizzle with the chocolate sauce and garnish with the remaining meringue drops.