Place the fructose and grapefruit juice into a bowl and whisk to combine

Add the butter and microwave in 30 second bursts until the butter has melted whisking each time

Lightly beat the egg yolks and then whisk in to the juice mixture

Microwave in 30 second bursts until the curd thickens (mine took 6 minutes)

Transfer straight away to a clean bowl and cover with cling film

Allow to cool before using

Using a pastry brush, brush the entire inner surface of 3 ramekins with the melted butter

Pour castor sugar into each ramekin and rotate until the butter is completely covered, shaking out the excess

Preheat the oven to 170° Celsius with a baking tray on the middle shelf

Whisk the egg whites to stiff peaks

Using a spatula fold the egg whites into the curd

Fill your soufflé dishes to the top and smooth off with a palette knife

Sprinkle the top with castor sugar and leave to melt for 1 minute

Thumb the edges and place into the oven for 18 minutes

Serve immediately