the logic: ladyfinger biscuits are basically little sponge biscuits, so why not make the sponge layer from scratch?
start a day before serving (or early in the morning!)
ingredients
sponge cake
3 eggs, separated
114g caster sugar, halved
1 tsp vanilla paste
90g plain flour
3/4 tsp baking powder
24mL milk (or soy milk)
optional and not traditional: 0.5 tsp cardamom
tiramisu assembly
2 eggs, separated
60g caster sugar
250g mascarpone, room temperature (homemade if you can! one day..)
1 tsp vanilla paste
about 1 cup strong, hot coffee (I used a moka pot, but espresso from a local cafe would be great too)
optional: 2 drops almond essence, or 30mL amaretto liquor
dark chocolate, for grating on top
method
cardamom sponge
preheat oven to 180°C
line a quarter sheet tray (~22cm x 33cm) with baking paper
in a medium bowl, whisk the egg whites (3) and half the caster sugar (57g) to medium peaks and set aside
in another bowl, add the egg yolks (3), vanilla (1 tsp) and remaining half of the caster sugar (57g), and whisk until light and fluffy
sift in the flour (90g), baking powder (3/4 tsp) and cardamom (0.5 tsp, if using) in batches, gently folding the mixture together in between
add the milk (24mL) and stir to just combine
gently fold in the egg white mixture in batches, mixing until just combined
pour into prepared tray and bake for 20-25 minutes
let cool slightly before removing from the paper and trimming off the edges (and top browned layer, for maximum coffee absorption)
cut the sponge into 2-3 rectangles that should be the same size as the base of your loaf tin (depending on the size of your loaf tin, and your preferred sponge:filling ratio)
assembly
optional: line a loaf tin with plastic wrap, for easier removal and serving
pour the coffee into a shallow dish and add the almond essence or amaretto if using
once the sponge cake has cooled completely, prepare the filling
place the egg whites (2) in a medium bowl, and whisk until they are lightly foamy
while whisking continuously, slowly sprinkle over half the caster sugar (30g)
continue until the egg white mixture hits firm peaks, then set aside
without cleaning your beaters, in a medium bowl beat together the egg yolks (2), vanilla (1 tsp), and remaining sugar (30g) until pale and fluffy
add the mascarpone and fold through until just combined
add the egg white mixture in batches, gently folding between until just combined
taking the first sponge cake rectangle, use a pastry brush or teaspoon to douse it with hot coffee and place in the bottom of the loaf tin
spread 1/3-1/2 of your filling on top (depending on how many cake layers you have)
repeat with the remaining cake layers and filling, ending on a filling layer
using a grater, cover the top with chocolate shavings
cover lightly with plastic wrap and refrigerate for at least a few hours or overnight
serve in generous slices