Other materials:

• 240 ml water
• 6 eggs
• 250 gram unsalted butter
• Hammer
• Tinfoil
• Skewer
• Tweezers
• Ruler

Preheat the oven to 180°C (convection oven 160°C) and lubricate the baking pans with baking spray. Prepare the buttercream by adding 200 ml of water to the 200 gram of Mix for Buttercream and put it aside for at least an hour. Mix the 400 gram of Mix for Sponge Cake with 6 eggs and 40 ml of water for 8 minutes on high speed until a smooth batter, and then for another 2 minutes on low speed. Divide the mix into the two baking pans and bake the sponge cakes for 30-35 minutes. After baking, let them cool down on a cooling grid.
Finish the buttercream as indicated on the package and add to taste the Sparkling Wine flavouring. Cut the sponge cakes both in half twice and fill them with the buttercream. Also cover the outside of the cake with buttercream. Knead the fondant well, roll out on a with icing sugar covered surface and cover the cakes with it. Cut off the remaining parts of fondant with a knife. Leave them in the fridge until further use.

Place 3 pieces of tinfoil on top of each other and form them into a bowl. Roll out a piece of fondant until a thickness of 4 mm, place this in the tinfoil bowl and let it dry well. Ideally you prepare this 2 or 3 days in advance to make sure it’s dry and hard. When the bowl has dried well, cut off a straight edge with the sugarcraft knife.

Place 4 layers of baking paper on the work surface. Take a big scoop-it spoon, fill it with half a bag of white isomalt and let it melt in the microwave. Pay attention to the fact that this will get very hot! Pour the melted isomalt on a baking paper and let it get hard. Add another half of the bag of white isomalt to the scoop-it spoon, add 1 ball of bleu isomalt to it and let it melt again. After melting, pour it on a new baking paper. Open the second bag of white isomalt, put half in the scoop-it spoon, add 3 blue balls and let it melt again. At last you let all the blue isomalt melt and you pour this on a baking paper again. Once all the isomalt has dried and hardened well, you place it in between two layers of baking paper and you smash it in pieces with a hammer. 

Take the cakes out of the fridge and put them on top of each other using the dowels and a cake board (cut off a piece out of the cake board already, cause there’ll be the geode). Once you’ve put the cakes on top of each other, cut out a piece of the cake with a sharp knife. Cover the hole with buttercream.

Place darkbleu pieces of isomalt in the middle of the hole, using tweezers. Fill the entire hole with pieces of isomalt, changing from dark isomalt in the middle to light in the outside. For the bowl you’ve made of fondant and tinfoil you do the same, only you’ll use piping gel to let the pieces stick. Cut the silver leafs in little strips of 1 cm, using the sugarcraft knife and a ruler. Lubricate the edges along the geode with water and place a strip of silver leafs on top of it. Push it a bit with a dry brush so it sticks well. If you wish to give the cake an extra effect, you may one to make spots on the cake with silver leafs. To do so, lubricate a piece of the cake with water and stick the silver leaf to it. Wipe out the silver leaf with a dry brush to create spots.

Place the geode on the top with a couple of skewers. You can also use a bit of royal icing to make it stick.