Lemon and passion fruit chiffon cake

Ingredients (cake, mousse line, 

• 3 lemons
• 180g self raising flour
• 1/2 tbsp baking powder
• 250g + 90g+50g caster sugar
• pinch of salt
• 100ml vegetable oil
• 8 large eggs
• 1 tsp vanilla extract
• 300ml milk
• 400ml double cream
• 40g icing sugar
• 2 passion fruits
• 50g corn flour
• 70g + 80g unsalted butter

Cake

1. Preheat oven to 170 degrees (150 fan)
2. Combine flour, baking powder, salt together in a large mixing bowl
3. Add vegetable oil, vanilla extract, juice and zest from 2 lemons and 5 egg yolks into the dry ingredients and mix until well combined (should be dropping consistency, if not, add 10-20ml of water and mix again)
4. Beat 6 egg white with electric whisk until foamy and add 1 tbsp of caster sugar at a time to the egg white until 250g has been added, whisk until stiff peak
5. Add 1/3 of egg white to the rest of the cake batter and very gently fold it in. Repeat until all egg white has been added 
6. Pour cake mix into a 23cm round bundt cake tin (without greasing or baking paper), or if you don't have a bundt tin, use a normal 23cm round tin and roll up a piece of foil to place in the middle of the tin, so the cake mixture can cling to it and climb up and also reduces the middle from dropping when taken out of the oven. 
7. Baking time of this cake is very variable. Bake for 45-70 minutes and keep a very close eye on the cake. Test with skewer after 35 minutes and use your own judgement from there. The cake should rise and increase in volume 
8. Cool the cake upside down over wired rack to prevent it from collapsing (hence no greasing or baking paper, or the whole cake will fall out). If cake has risen higher than cake tin, place 2 glass cups on either side of the cake tin and let the glasses hold the cake tin from the side
9. Let the cake cool for at least 1 hour

Mousseline

1. Beat 1 egg yolk and 1 whole egg together with 90g of caster sugar
2. Beat in 50g corn flour and zest from 1 lemon 
3. Heat 300ml of milk in saucepan until warm and add to the egg/sugar/cornflour mixture and whisk continuously 
4. Return the entire mixture to the saucepan over low-medium heat
5. Whisk mixture continuously until it thickens 
6. Remove from heat and stir in 70g butter until it has completed melted and incorporated into the mousseline
7. Let it cool completely 

Lemon and passionfruit curd

1. Beat 1 whole egg with 50g caster sugar 
2. Whisk in lemon juice from half a lemon
3. Put mixture over medium heat and stirring continously with wooden spoon
4. Reduce the volume down slightly and add 80g unsalted butter
5. Mix until melted and let it cool for 30 minutes
6. Add the passion fruit to the curd and mix well and cool in the fridge 

Assemble the cake

1. Cut cake horizontally in half
2. Place mousse line into the middle of the 2 halves
3. Whisk double cream with icing sugar until it forms stiff peak
4. Pipe or spread cream over the cake
5. Place the lemon and passion fruit curd over the top of the cake