Step 1

Choose a plate with a well around 2-5 cm smaller than your cake tin. Line the plate with cling film, carefully pushing out any air bubbles with your finger tips. Set aside.

Step 2

Place half of the orange juice in a small saucepan along with the orange zest. In a small bowl, whisk together the agar agar powder and water until smooth. Place the saucepan over low heat and bring to a low boil.

Step 3

Immediately add the agar agar mixture to the saucepan, stirring constantly. Cook for a further 2 minutes, then remove from the heat. Working quickly, add the remaining orange juice and mix thoroughly. Hold a fine mesh sieve over the lined plate (to catch the zest) and pour the jelly mixture through.

Step 4

Carefully transfer the plate of jelly to the fridge and leave to set.

Step 5

Preheat the oven to 175 °C fan. Line a 21cm (8.27 inch) cake tin with baking parchment on the bottom and sides.

Step 6

In a medium bowl, whisk together the soy milk, lemon juice, caster sugar, vegetable oil and vanilla extract. Set aside.

Step 7

In a separate medium bowl, sieve together the remaining sponge ingredients then whisk to combine. Add the wet ingredients to the bowl of dry ingredients and mix until combined to a loose batter.

Step 8

Pour the cake batter into the prepared cake tin and place in the preheated oven to bake for 30 minutes. While the cake bakes, make the syrup.

Step 9

Remove the cake from the oven and leave to cool for 10 minutes on a wire cooling rack, before removing from the tin and leaving to cool fully.

Step 10

Place the syrup ingredients in a small saucepan and bring to a simmer. Once all the sugar is dissolved, allow to simmer for 2 minutes then remove from the heat and set aside to cool.

Step 11

Once both the syrup and the cake are cooled to room temperature, brush the top of the cake with half of the syrup. Carefully flip the cake upside down and brush the underside with the remaining half of the syrup. Leave the cake upside down for the remaining steps.

Step 12

Remove the plate of jelly from the fridge and flip upside down onto the cake. Loosen the cling film and remove the plate. Make sure the jelly is in the centre of the cake then carefully remove the cling film. Place the cake in the fridge to chill while you make the ganache.

Step 13

Place the soy milk and coconut oil in a medium saucepan and place over low heat. Bring just to the point before boiling (the milk should be steaming but not bubbling) then remove from the heat. Add the chopped chocolate then cover the pan with a lid and leave undisturbed for 5 minutes.

Step 14

Remove the lid and whisk the ganache until smooth and glossy.

Step 15

Remove the cake from the fridge and place on a wire cooling over a large baking tray or bowl (this is to catch any extra ganache). Pour the ganache over the top of the cake, making sure it covers the sides evenly. Use a spatula to even out the top into a flat layer then use a skewer to make a grid pattern on the top (optional).

Step 16

Return the cake to the fridge to set for a further 30 minutes before slicing and serving.