Rhubarb and ginger meringues
Preheat the oven to 160°C, 325°F, Gas 3. Line a baking sheet with baking parchment.
Place the large egg whites in a large, spotlessly clean bowl, or in an electric food mixer, and whisk in the mixer, or using a hand-held electric beater, until the egg whites form soft peaks. With the machine still running, gradually pour in the caster sugar and keep whisking for about 5 minutes or until the meringue mixture forms stiff glossy peaks.
Spoon 4 large blobs of meringue, spaced well apart, on to the lined baking sheet. Using the back of your spoon, spread each blob into a round about 8cm (3in) in diameter, then use the spoon to make a well in the centre (in which the rhubarb fool will sit).
Place in the oven and bake for 10-15 minutes, or until they are crisp on the outside but still marshmallowy in the middle. To check that the meringues are done, carefully lift one off the baking parchment: if it comes away cleanly, it's ready. Remove the meringues from the oven and place them on a wire rack to cool. Don't worry if they crack a bit around the edges - it's part of their charm.
To make the rhubarb fool, put the trimmed rhubarb, the caster sugar and the grated root ginger in a saucepan with 25ml (1fl oz) water and cook, uncovered, on a medium heat for 4-5 minutes or until the rhubarb is stewed to a mush and the syrup is thick. Allow to cool, then fold the rhubarb mixture into the softly whipped whipped cream.
Place the meringues on a plate, spoon a lovely big dollop of the rhubarb and ginger fool over the top of each one and serve.