Place in a pan with the remaining ingredients and bring to a simmer.
Cook gently for 10 minutes or until the rhubarb is cooked, but some of the pieces remain firm.
Leave to cool.
Place the sugar in a bowl, then pour on the Champagne. Stir occasionally to help dissolve the sugar.
Whip the double cream until it's just holding it's shape. Stir in the skyr or yoghurt.
Pour in the sweetened Champagne, then whisk again until the mixture just holds it's shape.
Reserve 6 nice looking pieces of rhubarb and some of the liquid, then divide the compote between 6 small wine glasses.
Spoon the syllabub over the compote, then top with the reserved rhubarb and liquid.
If you're not using my recipe for homemade orange squash, you might like to add ½ a vanilla pod to the rhubarb whilst it's cooking.I keep a jar of golden caster sugar with spent vanilla pods immersed in it. This gives me wonderfully scented vanilla sugar whenever I need it.Can be made and assembled a few hours ahead of time.Please note: calories and other nutritional information are per serving. They're approximate and will depend on exact ingredients used.