Start by making raspberry jam by cooking together the defrosted raspberries and 2 tbsp caster sugar for 10 minutes and allow to cool down completely. Meanwhile, cut rounds of nonstick baking paper, slightly larger than your sponge. Spread over the melted chocolate and stick the sponge on top. Carefully lift onto a tray and place between 2 rolling pins to form tacos. Repeat to make 5 and allow it to set hard. Next, whip the double cream with the icing sugar and vanilla to soft peaks then add in the cocoa and continue to whip to stiff peaks. Pipe a little of the cream into the set tacos and spoon over the cooled down jam. Decoratively cover with the sliced strawberries and dust with extra icing sugar before serving.