For the Base
Put rhubarb, orange zest, juice and 75ml water in a saucepan and heat gently until completely soft.
Blend in Thermo coupe and pass through a fine sieve into a clean pan.
Return to the heat and add the cornflour mixture, stir until the mixture is very thick. Remove from heat and place cling film directly onto the purée and set aside.
In another pan dissolve 75g sugar with 6tbsp water over a low heat, boil to soft ball stage (115°C), Pour into the purée and mix well over gentle heat.
Transfer to a large bowl and cool completely.
For the Ramekins
Butter 8 ramekins with softened butter making the brush strokes vertical so as to not hinder the rising of the soufflés, Refrigerate until set.
Repeat the Buttering process, dust well with caster sugar and return to the fridge.
Pre-heat Oven at 190°C
To Finish Soufflés
Whisk the egg whites until stiff, slowly adding 25g caster sugar.
Beat one third of the stiff egg white into 275g of the rhubarb base to loosen the mix.
Very Gently fold in the remaining whites, trying to keep as much air in the mix as possible.
Spoon into the buttered ramekins, level the tops with a palette knife and run the tip of your knife just inside each rim to prevent the mix catching on the side.
Cooking
Set the ramekins on a tray and bake in the centre of the pre-heated oven, 190°C for 10 minutes.
The mixture should rise vertically about 2cm above the rim of the ramekin and should remain moist in the centre.
Dust with icing sugar, and serve with hot Rhubarb Flavoured Custard