Grind the rhubarb stalk in a blender until smooth.
Put the chopped rhubarb into a saucepan, cover with sugar and cook until a thick consistency is obtained. Then pour into molds and freeze.
Prepare beet oil separately. Beat beetroot juice and vegetable oil in a mixer.
To serve, put the popsicle on a plate, decorate with a spoonful of sour cream, fresh rhubarb, beetroot oil and a green pea sprout.