This isn't really a recipe - more of an excuse for having a very delicious drink.
3-6 stalks rhubarb
3 tsps sugar (to taste depending on amount of rhubarb)
2 tsps water
I bottle chilled prosecco/cava
Wash and cut up the rhubarb into 2 cm pieces. Place in a saucepan over a low heat. Add the sugar and water. Cook gently until the rhubarb is soft - taste for sweetness and add a little more sugar if you like. Leave to cool then strain through a fine sieve - so you are left with a pinkish syrup. Stir a little of the rhubarb pulp back into the syrup. Then add an inch or two of the rhubarb syrup to a glass and fill up with the chilled prosecco. Drink.