Clean the rhubarb and cut into pieces. Rub the zest of the lemon.
Boil the rhubarb in the water or a mixture of 1/2 l water and 1/8 l white wine with sugar, lemon zest and spices until the rhubarb disintegrates. Stir in the semolina, let it swell and then let it cool down well.
Beat with the mixer until foamy until a light mass is formed.
Serve with vanilla sauce, ice cream or liquid cream as desired.