Finally making the actual cake for this unique flavour request! Betty Boop avocado cake!
Reference from fanart drawing by Christina Kulzer
Take a peek at the layers!
I decided to include the element of gula melaka and toasted pecans in this cake as avocado alone is rather bland in taste. A little yuzu juice (or you may use lemon juice) was added to prevent oxidation of the avocado puree so it as a slight tang as well. This is a rather healthy cake as it doesn't use oil or butter but instead, avocadoes and plain yoghurt as fat sources! Very much more moist than typical chiffons!
The recipe for the cake and cream is shared in this post but I have made certain tweaks for it to be suitable for a large layered cake instead of a mini swiss roll so that it is easier to handle during assembly instead of breaking apart. I also increased the proportion of avocado in the filling.
I made two plain avocado sheet cakes and one patterned sheet cake.
Avocado chiffon cake recipe
Ingredients (makes one 25 x 30cm sheet cake):
Egg yolk batter
4 yolks
100g avocado puree*
1 tsp vanilla
1/8 tsp salt
8g gula melaka, finely chopped
1 tiny drop of pandan paste (optional)
80g cake flour
Meringue
4 whites
1/2 tsp cream of tartar
70g caster sugar
*Avocado puree
200g avocado puree
10g yuzu juice concentrate (or lemon juice)
150g plain yoghurt (I use Meiji's Bulgaria yoghurt)
Note: I made enough avocado puree for almost three portions of the sheet cake so please scale it down if need be.
Steps:
Please follow this post, except that baking time should change due to increase in volume.
Preheat oven to 180C bake 10min. Reduce to 160C bake for another 20 min.
Cool the cakes to room temperature. Cut to size you want (Mine is cut to 19x24cm). Cling wrap and freeze cakes. This will help with ease of handling during assembly. They are still super moist and soft despite reducing the liquid to flour ratio from my test bake!
Freshly baked sheet cake!
For the patterning, I used the method by Keem (see keempossible_2 Instagram account). I am not able to share recipe and method as I bought her video tutorial and you may contact her for it too 😊.
Remember to make a mirror image of the original when making patterns!
The pattern is subsequently covered with avocado cake batter but scaled down to 3 egg yolk portion
I used black edible marker to do the outlines as I find it has better control than painting. But this is just a personal preference. Betty's lips were added on post-baking with extra cake made from extra coloured batter. I always pipe out the excess coloured batter to bake for colour testing of paint during outlining/adding in of details post-baking so I just cut out the lips and white highlight and stick it onto the main cake with a little cake glue (you may use melted marshmallow too).
Avocado mousse
Ingredients:
150g whip topping (may replace with heavy cream but add sugar or increase amount of gula melaka)
180g whipping cream/ heavy cream (at least 35% fat)
5-6 gelatin sheets (about 10-12g), bloomed
120g chopped gula melaka/ coconut palm sugar (or to taste)
1//4 tsp kosher salt (1/8 tsp regular table salt)
2 small drops of pandan paste (optional)
100g plain yoghurt
300g avocado puree
15g 100% yuzu juice concentrate (or lemon juice)
Note: Prepare this only when you are ready to assemble with the cut sheet cakes, toasted chopped pecans, cakeboard and the assembly mould ready.
Steps:
1. Melt gula melaka and salt in heavy cream. Cool to room temperature, cling wrap and refrigerate overnight or at least 4 hours.
2. Prepare avocado puree by blending avocado with yuzu juice concentrate. Add yoghurt and blend briefly. Pass through fine sieve.
3. Bloom gelatin sheets in ice water. Squeeze put excess water. Melt bloomed gelatin using microwave or double-boiler. Set aside.
4. Whip cold gula melaka cream with whip topping (if using) until soft peaks form and you can start to see well defined lines in the cream as you whisk.
5. Add avocado puree (room temperature) to melted gelatin a little at a time and whisk together.
6. Add pandan paste to avocado puree gelatin mix.
7. Fold in avocado mix to whipped gula melaka cream in a few additions.
Assembly
1. Set rectangle mould frame over cakeboard. (I set the adjustable metal frame to be about 19x24cm) Line the insides of the frame with teflon sheet. Use a little oil to attach the teflon sheet to the frame but don't use coconut oil as it is a relatively high freezing point.
2. Place a frozen avocado sheet cake at the base of the frame.
3. Scoop some avocado mousse over the sponge cake and smoothen it out with a spatula or back of spoon.
4. Scatter some toasted chopped pecans. I didn't measure so up to personal preference. Omit if you don't like nuts.
5. Spoon a little mousse over the nuts and smoothen it out again.
6. Carefully place another frozen sheet cake over and press it in. Repeat steps 3-6.
After assembling the top patterned sponge
7. Chill in fridge for at least 3 hours or overnight for mousse to set. Carefully release the frame and peel off the teflon sheet.
8. Carefully slice off the four sides a little to reveal neat layers. Use a long serrated knife for this and it is important to make sure the mousse is completely set before you attempt to do this.
Just a little short video I made for fun of the process!
with love,
Phay Shing
