Yuzu for You

This birthday cake ends the birthday cake marathon I had for the past 2 weeks. Since the beginning of June I had been making birthday cakes for my boss, grandmother, myself, my co-worker, and yesterday, my other co-worker.  For some reason my boss hires 100% women Geminis to work for her (that makes 3, including herself, yes I work in a small company) So if you consider 1 woman is trouble enough and people born in within the horoscope have dual personality, that's 6 women in the house and 6 times the trouble.

Enough of that. So what did I make to end this marathon?

Yuzu Buttercream Cake
I was going to make half a batch of yuzu and half a batch of lime buttercream for the cake, although I am not sure about the favour pairing. I did a bit of taste testing, only to know that the limes I bought the other day are totatlly flavourless. Nonetheless, each of them only gave me a teaspoon of juice, even though they were in room temperature and I rolled them before juicing.

I have read quite a few recipes before attempting to creating this version. A few of them, like the basic swiss meringue by Martha Steward, are very easy to make, but I never liked the marshmellowiness of swiss meringue on its own.  Having known that the birthday boy adores sweets and creams, just like how he ate double portions of mango opera and triple portions of the strawberry custard cake, I have envisioned a buttercream for his cake. And checking the weather forecast of the day predicting 37 degrees in humidex, and knowing that they won't go home immediately after pick up, I need something sturdy enough to withstand the environment.

I finally settled down with this recipe, and have my own twist. It did not say in the recipe what type of meringue it is, I picked the Italian method knowing that it is the most stable. It did not explain the method of the custard base either, so I made up my own. It ended up with the following recipe which I would consider having a difficulty level of 9.9. I started making the buttercream at the start of the World Cup match between the Dutches and the Japanese, only to ruined a batch of syrup, almost flopping my meringue and the custard consistency looking more like I was whipping up a sponge cake recipe. Luckily I managed to get the cream done just when the soccer game ended. That's 2 hours of hard work!

OK, here is my version and method if you want to challenge yourself.

Yuzu Buttercream
(inspired by 獨角仙)
I have recalculated the recipe so that easier to manage by using whole eggs.
A (custard):

• milk 100g
• vanilla extract a few drops
• egg yolk 57g (about 3 large yolks)
• sugar 96g

B(Italian meringue):

• egg white 66g (2 large egg whites)
• a pinch of salt
• sugar 123g
• water 30g

C:

• butter 443g (yes, that's a pound minus 11g of butter)

D (flavour):

• yuzu syrup, to taste (about 3 to 4 tbsp)
• lime/lemon juice, to taste  (about 2 tbsp)

Method:

Custard A:
Heat milk with sugar until scalding. Whisk yolks and vanilla in a heatproof bowl. Temper the yolks with the hot milk. With an electric mixer, whisk the custard on a double boiler (or theoretically return to the pot works, but it's easier to beat) until it foams up like sponge cake consistency. Remove from heat and keep beating until it cools. Cover and set aside.

Meringue B:
Add a pinch of salt to the room temperature egg whites and start with low speed whisk the whites for a few minutes. When it starts to foam, gradually increase speed. While the egg whites are whisking, boil sugar and water to 118 degrees C (reduce heat when it gets above 100 degrees). When the whites turn into soft peaks, gradually drizzle the sugar syrup into the meringue. Keep beating until it becomes glossy and very stiff peaks.

Butter C:
Dice into small pieces.

Flavouring D:
Chop up yuzu syrup in a food processor until it turns into a creamy colour. Pass syrup through a fine sieve to elliminate any zest. Discard the zest or keep it for another use.

Assembly:
Fold meringue into the custard in batches. Slowly add butter into the mixture and mix with an electric mixer. Add only a few pieces at first, as it is prone to break. If it looks like it is starting to curdle, stop adding butter and keep beating. Once it's stable, you can add butter at a faster pace.
Add flavouring and adjust according to taste.

I made a fold on the lid of a regular cake box to accommodate the extra tall pyramid!