Kefir and yoghurt and buttermilk
These are the cultured friends in your fridge. They
bring the tang. They’re not always interchangeable,
but if you don’t have buttermilk or yoghurt, stir
10 g/ml (¼ oz) lemon juice into 90 g/ml (3 oz)
milk and stand for 10 minutes to start curdling.

Eggs-pert
Eggs are a multi-talented baking building block.

Whole eggs emulsify batters, egg yolks add
tenderness, richness and silkiness, and the whites
are amazing, with their ability to multiply by
around six times in volume when whipped!
If your baking budget allows, please prioritise
buying truly free-range eggs, and choose ones
with minimal hen count per hectare (or maximal
roaming space). Cage eggs are a cruel business.

And very good eggs will bring a better, sunny
flavour and hue to your bakes (they also
contain more nutrients, and your conscience
will rest easy).

I always weigh eggs, egg yolks and egg whites –
without the shell – because eggs can be different,
and egg companies can have a sizeable difference
in their sized eggs – to the point where you may
be adding a whole extra egg to a batter when
making an egg-heavy cake. Weighing eggs really
shines when I want to use irregular backyard or
farmers’ market eggs. I don’t have to size them,
just crack and weigh the goodness inside. My
egg formula is for an egg weighing 59 g (2 oz)
with shell > remove shell > 50 g (1¾ oz). The
white is approximately 30 g (1 oz) and the yolk is
approximately 20 g (¾ oz), but you can encounter
smaller yolks (another reason to weigh). I allow
a little difference (I swear I’m not a monster) – if
the egg/yolk/whites’ weight is 10 g (¼ oz) under
or over, continue. If you need more or less, break
up the whole egg well with a fork and adjust the
amount as needed. If you pour off the excess of
a freshly cracked egg without breaking it up first,
you are usually just pouring off the egg white,
which can affect baking.

Cold egg or warm egg? For whipping: cold
egg/whites/yolks have more stability and less
volume. Unchilled, you get more volume and less
stability – but overall, the difference is negligible.

When adding whole eggs to creamed butter
bases, always warm the whole egg (in its shell)
in hot tap water for around 5 minutes. This will
create a stable temperature for the butter–egg
emulsion. You can warm cracked eggs in a bowl
over a barest-of-steamy double boiler, stirring
slowly and constantly to avoid scrambling.
egg in shell ― 59 g (2 oz)
egg out of shell ― 50 g (1¾ oz)
egg white ― 30 g (1 oz)
egg yolk ― 20 g (¾ oz)