Method

1. Begin by making the clementine curd. In a small saucepan, mix the zest and juice of the clementines and lemon, the egg, egg yolks and sugar. Cook on a medium-low heat for 10-15 mins, stirring constantly, until the curd is thickened and you can draw a line through it with your spoon. Once it has reached this stage, remove it from the heat and beat in the cold butter. Cover and set aside in the fridge to cool completely.

2. For the sponge, heat the oven to 180C/160C fan/gas 4 and line a 25 x 40cm Swiss roll tin with baking paper. In a large bowl, whisk the eggs, sugar and vanilla bean paste together with an electric whisk until it has tripled in volume and leaves a 5-second ribbon on the top of the mixture when you raise the beaters.

3. Sift over the plain flour and gently fold it in with a spatula or a large metal spoon, being careful not to knock out the air. Gently pour it into the lined tin and smooth it out. Put it in the oven for 15 mins, or until golden and spongy to the touch. While the cake cooks, take a large sheet of baking paper and dust it with caster sugar.

4. When the cake is done, turn it out onto the baking paper with the caster sugar on and cover it with a tea towel. Allow to cool slightly and then roll it up from one of the short sides. Leave it like this until cool.

5. Whip the double cream with the vanilla bean paste, clementine zest and sifted icing sugar until it holds a soft peak.

6. Unroll the cake and using a palette knife, spread the curd onto the sponge, right up to the edges. Spread the cream on top of the curd and re-roll tightly, using the paper to help you, putting it seam-side down. Put in the fridge while you make the icing.

7. In the bowl of a stand mixer, or using electric beaters, add the well-softened butter and vanilla bean paste. Whip it until it is very creamy and pale, scraping the sides down a few times. Add the sifted icing sugar a large spoonful at a time. Then, add the melted white chocolate and milk and whip until it is creamy and smooth.

8. Remove the yule log from the fridge and put it onto a serving plate. Use a palette knife or spatula to smooth the icing onto the log, including over the ends. Use a fork or palette knife to make tree like markings along it. Sprinkle generously with icing sugar and shimmer spray. Serve with strips of clementine zest for a really festive look. Will last for 3-4 days in an airtight container.