EQUIPMENT

Use two 7 inch (18cm) or 8 inch (20cm) pans

INGREDIENTS

For the cake

140g (1 cup) all-purpose flour

120g  (½ cup + 1 tbsp) white granulated sugar

3 medium eggs

135g (1 stick + 1 tbsp) softened unsalted butter

45g (3 tbsp) lemon juice

Zest of 2 lemons

Pinch of salt

½ tsp baking powder

¼ tsp Vanilla extract

Yellow and green gel food coloring

1 tbsp apricot jam

For the foam (the soap)

1 egg white

2 tbsp white granulated sugar

½ tsp lemon juice

INSTRUCTIONS

Make the yellow and green cakes

In a large bowl, cream together the softened butter, sugar, lemon zest and vanilla extract.

Add the eggs one at time, mixing well after each addition.

Sift in the flour, salt and baking powder. Add the lemon juice, and mix until just combined and smooth. Do not over-mix. Don’t worry if the mixture looks like it’s curdled. That’s due to the citric acid in the lemon juice. It won’t affect the texture of the final cake.

Pour one third of the batter into a separate bowl - around 200g to 220g, and set aside.

To the larger (two thirds) portion, add yellow food coloring and stir to achieve an even color.

To the smaller (one third) portion, add the green food coloring and stir to achieve an even color.

Pour each portion of batter into separate cake pans lined with parchment paper. Because there is a small quantity of the green batter, you will need to spread it out evenly.

Bake both cakes in a pre-heated oven at 320°F (160°C).

The green cake will cook more quickly than the yellow cake. So, take the smaller, green cake out after around 10-12 minutes. Take the larger, yellow cake out after an additional 5 minutes (for a total cooking time of 15-17 minutes).

Allow both cakes to cool completely.

Assemble the illusion cake

Spread the apricot jam over the top of the yellow cake. The jam will act like glue. Place the green cake firmly on top of the yellow cake.

To create the “scrubber” texture on the green cake, shave of the top crumb of the cake using a serrated knife. See the video for the precise details of the technique.

Trim the sides of the cake, and cut into six dish-sponge-size rectangles.

Make the “soap” foam

Take a small, clean bowl, and add the egg white, lemon juice, sugar. Whisk like you would a meringue, but stop whisking as soon as soap-like bubbles form. Spoon a little of the “soap” foam on the dish sponge to finish the illusion.

Tips

Make the soap foam just before serving - it won’t hold its structure for long.