Fill a medium saucepan with 1 to 2 inches of water and bring it to a simmer over high heat; reduce the heat to low and keep the water at a bare simmer.

Place all of the ingredients except the butter in a large heatproof bowl and whisk to combine. Set the bowl over, but not touching, the simmering water and whisk constantly until the yolks thicken and the mixture forms ribbons when the whisk is lifted from the bowl, about 7 to 10 minutes.

Remove the bowl from the saucepan and whisk in the butter one piece at a time, waiting until each piece is completely melted and incorporated before adding another.

Set a fine-mesh strainer over a medium bowl. Strain the curd into the bowl; discard the solids left in the strainer.

Press a sheet of plastic wrap directly onto the surface of the curd to prevent a skin from forming. Refrigerate until set and chilled, at least 3 hours.

Put the blackberries, honey and vanilla pod and seeds into a medium sized saucepan over a low heat. Cook gently, stirring occasionally, for a few minutes until the berries have released their juices and softened, but still hold their shape.

Remove from heat and pour the berries and juices into a strainer set over a bowl. Once the excess syrup has drained off, spoon the berries into a dish or container and put into the fridge to chill until needed.

Preheat the oven to 200°C (400°F). Grease and line a 23 x 33cm (9 x 13 inch) Swiss roll tin with baking paper.

In a large, clean bowl, whisk the egg whites with an electric whisk on medium speed until soft peak stage. Turn the speed to high and gradually add the sugar, beating well between each addition. Continue whisking until all the sugar is incorporated and the mixture is extremely stiff and glossy.

Spread the meringue mixture evenly over the base of the tin and sprinkle over the almonds. Bake for 10-12 minutes or until golden, then lower the temperature to 160°C (320°F) and bake for a further 20 minutes until crisp on top.

Remove the meringue from the oven and turn it out, almond-side-down, on to a sheet of nonstick baking paper. Peel off the baking paper and leave the meringue to cool.

Lightly whip the cream (it should be soft rather than stiff).

Using an off-set spatula, spread the lemon curd evenly over the cooled meringue, then spoon the cream over top. Scatter the softened blackberries over top.

Using the baking paper as a guide, roll up the meringue from one of the shorter sides to form a roll and place it seam side down on a serving platter. Finish with a light dusting of icing sugar, if you like.