Ingredients

• 160g/5¾oz walnut halves
• 140g/5oz caster sugar
• plus extra for dusting
• 4 free-range eggs
• 140g/5oz plain flour
• plus extra for dusting
• 3 tbsp unsalted butter
• melted
• plus extra for greasing
• 2 tsp instant coffee granules
• 2 tsp boiling water
• 170ml/6fl oz double cream
• 25g/1oz icing sugar
• plus extra for dusting

Directions

• Preheat the oven to 200C/180C Fan/Gas 6. Butter a 34x22cm/13x8½in Swiss roll tin and line with baking parchment.
• Roast the walnuts in the oven for 5 minutes
• or until a shade darker and aromatic. Let cool
• then finely chop half of the walnuts.
• Using an electric whisk or stand mixer with the whisk attachment
• whisk the sugar and eggs together until pale
• thick and creamy and at least doubled in volume. This will take 8–10 minutes.
• Sift a few tablespoons of flour at a time into the bowl
• and very gently fold into the mixture using a large metal spoon. When all the flour has been incorporated
• gently fold in most of the chopped walnuts and the butter. Be patient and do not knock out too much air.
• Transfer the mixture to the prepared tin and smooth out using the back of a spoon. Bake for 10–12 minutes until golden-brown and slightly springy to the touch. Do not leave to cool.
• While the sponge is still warm
• place a large sheet of baking parchment on your work surface and dust liberally with caster sugar. Supporting it with your hand
• carefully invert the sponge onto the parchment. Gently peel off the top layer of parchment. Trim the very outer edge of the sponge with a sharp knife. Score a line 2cm/¾in in from the short end of the sponge closest to you
• but do not cut all the way through. Using the parchment
• tightly roll up the sponge and leave to cool
• seam-side down.
• For the filling
• mix the coffee and boiling water to form a paste. In a large bowl
• whisk together the cream
• icing sugar and coffee paste until soft peaks form. Cover and refrigerate until needed.
• Gently unroll the cooled sponge. Spread the cream over the surface
• leaving a 1–2cm/½–¾in border all round. Scatter over the remaining chopped walnuts. Roll up the sponge again and place on a serving plate
• seam side down. Arrange the whole walnuts on top and dust with icing sugar before serving.