Peel the washed rhubarb and cut into pieces about 3cm long. Gently simmer the rhubarb peelings with the oranges, vanilla pod, white wine and lemon peel, cinnamon and sugar for about 10 min over a gentle heat.
Strain the rhubarb stock through a sieve and gently simmer the rhubarb pieces in it for about 5 min on low heat. Remove the rhubarb and leave to cool.
Add 2/3 of the strawberries to the rhubarb stock and fill up with the orange juice. Blend finely with a hand blender and leave to cool.
Cut the remaining strawberries into slices. Pour the champagne into the cold soup.
Divide the chilled soup evenly into deep plates and garnish with rhubarb pieces and strawberry slices.
and garnish with strawberry slices.