LEGO-Shaped Chocolate Mousse Cake

The LEGO-shaped chocolate mousse cake is a sweet and delicious recipe that combines all the fun of eating a big LEGO block and learning to use the ultimate "Maker" procedures.

This make is divided into 2 parts, the "Preparation" one, in which we'll make the design and fabrication of the positive and negative molds, and the "Delicious" elaboration, which includes all the recipes for the mousse and the cake bases.

This project is intended to be modular! So take it all or just the part that suits your supplies or habilities the best!

Have fun, enjoy the process and LET'S MAKE IT!

Mold-making tools:

1. 3D printer
2. Hot glue gun

Kitchen tools and utensils:

1. Spatula
2. Whisk
3. Various sized bowls
4. Rectangular Tray or Mold (Suitable for the oven)
5. Electric mixer [ If you want to go faster ;) ]
6. Sieve
7. Baking paper
8. Scale
9. Spoons
10. Knives

Materials to make the Mold:

1. PLA filament
2. Food safe elastic mold fabrication silicone
3. Foamboard or Cardboard
4. Hot glue
5. Skewer

Ingredients for the Sponge cake:

1. 4 eggs
2. 150g of Wheat flour
3. 150g of sugar
4. Berry jam or the flavor of your preference

Ingredients for the Chocolate Mousse:

1. 150g of 70% Chocolate
2. 35g cream + 225g cream (Same cream but separated in different bowls)
3. 35g whole milk
4. 1 egg yolk
5. 2 gelatine sheets

Firstly, open Fusion 360 and create a new project. Then, once it's ready, we click on the "Top" view in the corner cube, and in the menu, we "Create a new sketch". Now we can start drawing our LEGO 4x2 Shaped block.

Following the sizes that we can find all over the internet, we draw a rectangle (15.8mm by 31.8mm) and extrude it by 9.6mm. We can also make a chamfer intended to make the mold easier to remove.

Once created the base shape, it's just needed to add the mounting dots at 3.9mm squared from the corners, 8mm separating each, and 4.8mm in diameter.

After the dots are drawn in the sketch, we extrude it at 1.8mm, and for the same reason as the chamfer, we add a fillet of 0.5mm.

Now we export the piece as a ".3mf" or ".STL file", so the slicer of the 3d printer knows how to read it and open it. In there, we will set the size that we'll use to make the mold.

Once we have the 3D model, we import it to our slicer, in this case, is the Ultimaker Cura. From there we change the size to our desired one, in our case 50mm in width, changing the height and length accordingly (Uniform Scaling).

Making the mold is an easy task, we have to create, firstly, the enclosure. For the size printed, we'll need one sheet of A4-sized foamboard. We cut and glue the 5 pieces of foamboard (4 walls and the bottom part) making the box 2mm oversized for each side to make the mold walls with the proper stiffness and also with the adequate flexibility to not disturb the mousse.

Now we have to mix well the food-safe mold-making silicone and pour it into the case from an approximate height of 30cm to ensure we get rid of all the bubbles.

Let it cure for the time it says in the silicone instructions and de-mold the piece. Congratulations! Now you have a mold to make this giant delicious LEGO mousse.

Firstly, we will separate the egg whites from the egg yolks. Whip the egg whites until you can put the bowl upside down without the egg falling. That's the texture we are looking for (also forming peaks on the whisks).

Secondly, in a separate bowl, sieve de flour and add the sugar, the egg yolks and mix. Then incorporate the egg whites into the flour mixture bowl making enveloping movements, with the help of the spatula. You will obtain a smooth batter.

Place and spread the batter on an oven tray covered with baking paper, until it has a thickness of 0,5 cm (approximately). Then, introduce the tray into the oven and cook the sponge cake for about 5 minutes at 180ºC.

Finally, let the cake cool down on an oven rack.

In a bowl filled with cold water, place the gelatine sheet and let it hydrate during the time it takes to make the other steps (5-10 min approximately).

Fill half of the saucepan with water and place a glass bowl on top. Blanch the egg yolk while continuously whisking until it creates bubbles. Then, incorporate the milk and the 35g portion of the cream and heat the mixture until it achieves a temperature of 60-70ºC.

Mince the chocolate in a bowl. Then, add the drained gelatine sheets and the hot mixture to it. Whisk it until a soft texture is formed without solid bits left. Set aside.

Whip the 225g portion of the cream. then add it gently to the chocolate mixture bowl with enveloping movements. Once the color is consistent let it rest in the fridge for 10 min.

Now that we have the sponge cake and the liquid mousse made, we'll assemble the final LEGO-shaped chocolate mousse cake!

Make two cuts equally sized of the sponge cake in a slightly smaller shape than the mold size to let the mousse make the walls and cover the layers.

Fill the mold bottom with the mousse mixture. Then, add one cut of the sponge cake, spread the jam on it, and cover it with the other cut.

Top the mold with the rest of the mousse mixture. Let it rest in the freezer.

Once the mousse solidifies, de-mold it and place it on a plate.

Let it rest for 3-5 min to acquire the proper mousse texture and ENJOY IT!