Chocolate and orange yule log

serves 8

For the swiss roll:

 50g unsalted butter, plus extra for greasing

 4 large eggs

 150g caster sugar, plus 1tbsp for dusting

 1tsp vanilla extract

 100g plain flour

 25g cocoa

 Zest of 1 orange

 ½ tsp baking powder

 Pinch of salt

For the Filling:

 100g dark chocolate, chopped

 200g unsalted butter, softened

 225g icing sugar

 2tbsp cocoa, sifted

 2tbsp golden syrup

 2tbsp full-cream milk

 1tsp orange extract

 ½ jar marmalade

to decorate:

 100g mixed peel

 Edible gold lustre spray

1 Heat oven to 180C/ Gas 4. Grease a 40x30cm Swiss roll tin and line with baking parchment.

2 Melt the butter then leave to cool slightly. Put the eggs, sugar, orange zest and vanilla into a bowl and whisk until the mixture is pale, thick and trebled in volume – about 5-6 minutes.

3 Sift the plain flour, cocoa, baking powder and salt into a bowl and gently fold in using a large metal spoon.

4 Gently pour in the cooled, melted butter and fold in.

5 Spoon or pour the batter into the prepared tin and level with a palette knife. Bake on the middle shelf of the preheated oven for 9-10 minutes or until well-risen with a light crust and the cake springs back when lightly pressed with your finger.

6 Leave to cool in the tin for 1 minute. Meanwhile, lay out a large sheet of baking parchment and scatter with 1tbsp sugar. Carefully turn the Swiss roll out on to this and peel off the lining paper. Lay a clean tea towel on top and, starting at one of the shorter edges, roll the cake into a tight spiral with the tea towel inside the roll. Leave until it has gone completely cold.

7 To make the buttercream, melt the chocolate in a heat-proof bowl over a pan of barely simmering water. Stir until smooth, remove from the heat and cool slightly.

8 Beat the butter until pale, light and creamy and gradually add the icing sugar 1tbsp at a time, scraping down the sides of the bowl. Add the cocoa, golden syrup, milk and orange oil and mix until smooth. Add the cooled, melted chocolate and mix again until smooth.

9 To assemble the roulade, carefully unroll the cooled cake and remove the tea towel. Spread a thin layer of marmalade across the sponge. Then spread over four generous tablespoons of buttercream.

10 Using the paper to support the cake, roll it back into a tight spiral and transfer to a serving plate. Cover the whole roulade with more buttercream, spreading it smoothly.

11 Put the mixed peel and gold lustre into a bowl and tumble together, until the peel is shimmering. Sprinkle on top and serve.

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