Don’t leak: how to win
at liquid-filling tart life
Avoid tart-ache when a baked brittle crust meets
a totally liquid filling, such as with the Lemon
cream tart (page 97), Chocolate rum maple
pecan pie (page 115) or the Vanilla malted milk
custard tart (page 122). Skip this how-to for
Fig, brown butter + almond frangipane tarts
(page 109) or Banana cream pie with sesame
tofee crunch (page 126), where the filling is
thick or bakes like cake (not custard). They
can handle cracks.

Patch it real good Sometimes you will have a

crack-less baked crust. Gold star! Go to the next
step. If there are cracks, however, take teaspoonfuls
of raw dough left from rolling and massage between
your fingers to soften. Ensure your crust is
lukewarm to cool. Hot crusts are more fragile.

If you don’t have any leftover dough, make a thick
patching paste with 20 g (¾ oz) plain (all-purpose)
flour and 10 g (¼ oz) soft butter and a sprinkle of cold
water. Massage together with your fingers and push
it into the cracks.

Lightly (or you risk making a bigger crack) smear
or press little flat discs over any large fissures or
breaks where the liquid filling is likely to escape.
I get right down at bench level to eyeball the tart
side like a I’m a forensic investigator. If I even
suspect a crack, I’ll patch. Use the raw dough
sparingly – too much will leave you with unpleasant
undercooked dough lumps in the finished tart.

If you build it If an edge section has slumped

dramatically when baked, use softened raw dough
to build up the edge, so it’s even with the higher
edges. This means you won’t have to skimp on
the filling – you can only fill a tart as high as its
lowest side. The section will bake with an obvious
top of raw-ish dough, which I would happily eat,
but at the shop I cut that piece out and saved it
for staff snacks.

Egg white wash Like a waterproof varnish on

wood, this wash seals any fine cracks and forms
a protective coat that slows down the crust
softening after baking. Break up a gloopy egg
white with a fork or a small whisk to make it
foamy and brush-able. If the crust is hot from
blind baking, the egg white may leave white
cooked smears. This is okay, and it will meld with
the filling. Just avoid big slurps of egg white, as
it will bake like an egg-white omelette inside the
tart. Eew!
Brush a moderate amount gently over the entire
inside of the crust. If the crust is warm, let it dry at
room temperature. If the crust is cool, set the egg
white–washed crust in a low 120°C (250°F) oven
for 2–3 minutes. This crust warmth will also jump
start the filling baking near the crust – another
helpful sealing step.

Don’t heat too long, because the egg white can
contract and pull the crust with it, making it appear
like a dried-up lake bed. If this happens, egg wash
again. Don’t scrape off the previous layer, as you risk
creating a hole.

Oven rack ready
Before preheating your oven, arrange the oven
racks so your baking shelf is centre or lower, and
remove the upper racks so you can manoeuvre a
jug of filling while the crust is in the oven. Trying
to lift a crust full of sloshy, fluid custard is like
watching an approaching avalanche – tragedy
imminent! I also don’t like to pull the rack out
to fill. If the rack snags on the push back in, the
filling can slosh between the crust and tin, making
tart removal ever so difficult. The next step is my
most trusted filling method.