1. Heat the oven to 180C/160C fan/gas 4. Grease two 20cm Victoria sandwich tins with butter and line with baking parchment. In a large mixing bowl, beat the butter, caster sugar and muscovado sugar with an electric mixer until light and fluffy, then whisk in the eggs one at a time, adding the Dr. Oetker Madagascan Vanilla Extract with the last one. Finally, beat in the flour. Divide the mixture between the cake tins and bake for 25 mins until golden in colour and a skewer inserted into the middle comes out clean. Remove from the oven and allow to cool, before turning onto a wire rack to cool completely.
2. To make the buttercream, in a large bowl beat the butter with an electric whisk until pale and fluffy. Add half the icing sugar and combine, before adding the rest and beating again until lighter in colour. Mix in the Dr. Oetker Fine Dark Cocoa Powder, along with a little milk to loosen, if needed.
3. When the cakes are cool, place one on a serving plate or cake stand and top with 6 tbsp of buttercream. Smooth it out, then place the other cake on top. Put the rest of the buttercream on top of the cake, smoothing down the sides to cover completely. Flatten off the top, then swirl with a palette knife to recreate the inside of a log. Chill in the fridge to set.
4. Take 50g of the white Dr. Oetker Ready to Roll Fondant Icing and make 6 varying sized bases for the mushrooms. Next, roll 6 pieces of the red fondant into different sized balls, then flatten slightly and press out the sides to create toadstool caps. Pop them on top of the bases, before using the remaining white icing to roll lots of tiny balls to press onto the toadstool caps.
5. Line a large baking tray with baking parchment. Microwave the dark chocolate in a microwavable bowl in 30 sec bursts until melted. Using a paint brush, paint the chocolate onto the paper, roughly drawing horizontal lines and random rings and dots to emulate the look of bark. Leave to chill in the fridge while you melt the white chocolate using the same method as above.
6. When the white chocolate has cooled, pour it over the tray with the set dark chocolate and gently spread with a palette knife so it’s approximately 36cm x 25cm. Leave to set completely. Once set, cut in half lengthways, then cut each half into 7 rectangles, so you have 14 pieces of bark. Place the bark around the side of the cake, finishing with the toadstools and a few sprigs of rosemary or pine.