Slice of Cheese - Cake

This project shows you how to create a food safe mould using two easy to get ingredients. It's a cheaper alternative to food grade silicone. You will be able to cast chocolate moulds, cake decorations or weirdly shaped desserts. I'm making a Swiss cheese slice out of yellow chocolate, with sponge, strawberry jello and strawberry mousse inside.

Unlike proper food safe silicone, this gelatin-glycerine 'silicone' can be melted over and over again, however it will go bad after a few days and you will have to throw it away. You can cast 3D printed models, smooth plastic objects, sculptures made out of fondant. This 'silicone' doesn't set extra rigid, it has some flexibility, which helps when it comes to removing models from moulds, but the one disadvantage is that it doesn't handle overhangs well. If your model has an overhang or a deep ridge, your mould might rip.

FOUR SERVINGS

FOR TWO GELATIN MOULDS:
600g food grade glycerine
100g powdered, unflavoured gelatin
500ml cold water

FOR CAKE:
2 eggs
70g sugar
50g flour
20g cornstarch
pinch of salt
few drops vanilla extract

FOR MOUSSE:
300g strawberries, washed and cut up
1/2 cup sugar
100g white chocolate
1tsp unflavoured gelatin
250ml whipping cream (36% fat)

ADDITIONALLY:
Yellow candy melts
Strawberry jello

Cling film, glue gun, 3d printed model

3D print your model model, best quality print possible and good amount of infill, to make sure all those dips at the top print properly. Take a look at the second picture, this test mould was made using a very poor quality (0.3mm layer height) model. You can see every tiny ridge in the jelly mould and once poured, chocolate shell would show all those layers as well.

This mould is perfect for the exact model size I 3D printed and will fit half the amount of jello-glycerine.

Print this rough sketch and transfer it on a piece of thin cardboard. Outline, cut out and use a craft knife to gently score where marked. Use a glue gun to put it together. It doesn't have to be perfect, just sturdy.

Use two layers of cling film to line the inside of the cardboard mould. Place the model inside, position it as evenly as possible and, since we can't use glue, place something heavy on top (a jar or a can will do). Pour jello-glycerine 'silicone' HALFWAY THROUGH only and leave to set (30 min in cold kitchen or 15min in the fridge will do, doesn't have to be fully set). Remove the jar/can from the top, fill the mould with more 'silicone' and leave it in the fridge to set for 1 hour.

I used PLA for my model and I didn't have to use any lubricant to make sure jello won't get stuck. If you are not sure you can brush the model with a thin layer of oil to ensure the model will pop out of the mould.

Use a large, wide saucepan, it will be easier for gelatin to bloom. Pour 500ml cold water in, sprinkle 100g gelatin and stir it in quickly, we want all the gelatin granules to be covered in water. Leave it to bloom for 10 minutes. Put the saucepan on the stove and heat it over medium heat, stir constantly until all gelatin is dissolved, but DON'T bring it to a boil. Take it off the heat and add 600g glycerine, stir well and leave it to cool to room temperature.

To make a sponge cake, separate egg whites and egg yolks. Measure flour and cornstarch and mix them together in a separate bowl. Measure sugar.
In a medium bowl, whip egg whites to soft peaks, add about half the sugar and continue whipping until egg whites are stiff and remain in the bowl when turned upside down. In a large bowl, whip egg yolks with the remaining sugar, add a pinch of salt and vanilla extract. Once egg yolks are pale and tripled in size, add sifted flour and cornstarch and whip it together. Cake mixture will be really thick at this point, so add about 1/3 of the whipped egg whites to loosen it up and whip until smooth. Add remaining egg whites and gently fold them in.

Pour into a small baking tin lined with parchment paper and bake at 180°C for 20-25 min. Leave it to cool down in the tin.

Once cooled, I used a serrated knife to cut the top off and then cut the cake up into triangles.

I used a store bough jello packet to make a concentrated, stiff jello layer. My jello packet instructions said to dissolve it in 500ml of water, but I only used 250ml. Once dissolved, I poured it into a flat bottomed container lined with cling film. I poured just enough to get 1cm thick jello layer. I put it in a fridge to set and then cut triangles small enough to fit into the mould.

Put strawberries, sugar and 2TBS water in a saucepan, cook on low heat until strawberries soften and become mushy. Push them through a sieve or use a food processor to blend them into puree. Place strawberry puree back into a saucepan and add chopped chocolate. At the same time, in a small bowl, combine 1TBS cold water and 1tsp gelatin, leave to bloom for 10min.
Heat the puree and chocolate over low heat until chocolate melts, add bloomed gelatin and stir well. Leave it to cool down to room temperature.

Whip cream to stiff peaks and put it aside.

To create a mousse you simply have to mix the strawberry-chocolate puree and whipped cream. However, you have to do it directly before you are ready to assemble the dessert. You have to have the mould ready and already coated in chocolate and your cake and jello triangles have to be cut up.
If you only have two gelatin-glycerine moulds and are making 4 desserts, you will only be able to work on two desserts at the time. If that's the case, you will have to weigh whipped cream, divide it and keep it in two separate bowls. Same goes for strawberry puree, keep half in one bowl, half in the other.

Once you are ready to assemble the dessert, pop the first puree bowl in a microwave for a few seconds to melt the gelatin again, cool it to room temperature and whisk it into whipped cream. Transfer to a plastic piping bag and quickly assemble the dessert.

To remove the original model out of the mould you have create a zig-zag cut in a curved wall (see picture) and then gently ease the walls away from the model.

For two moulds, melt 150g candy melts. Use microwave or double broiler.

Moulds will be quite cold. Once poured, melted chocolate will set almost immediately, so you will have to work quickly to spread chocolate all over the mould. Use a spoon to distribute chocolate evenly. Put in a fridge for 15 min to set fully. If you missed some spots, you can add more chocolate once the first layer is set.

Use a piping bag to pipe a layer of mousse first and add a triangle of jello on top. Gently press jello into the mousse. Add another layer of mousse and a triangle of cake, gently push the cake into the mousse.

Make sure filling isn't overflowing, you need enough space to add a layer of chocolate on top later. Chill in the fridge for 30min. Add a layer of chocolate to cover the bottom of the dessert and level it as best as you can. Chill for further 15-30min before removing from the mould.

Take the mould out of the fridge and remove the dessert immediately, keep it as cool as possible. Use a knife to scrape any imperfections, particularly at the bottom.

Put the dessert on a piece of parchment paper to prevent sticking and leave it in the fridge until serving.