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Last week was the Jewish festival of Passover, when it is forbidden to eat any leavened products. That means all raising agents, as well as flour, are off-limits. Even so, there are dozens of traditional Passover cakes and biscuits, and mastering the techniques behind them can help you with all sorts of other bakes too. My go-to is the humble cinnamon ball, a sweet, soft biscuit with a crisp outer shell.

In general, the key to achieving airiness in your bake without raising agents will come down to using egg whites. These essentially consist of proteins and water, and as you whisk them, the curled-up proteins unravel and stretch out. These strands can bond with each other, trapping bubbles of air around the water, which allows the egg whites to expand to up to eight times their volume.

Unfortunately, egg whites are notoriously tricky to handle. Over-whisk, and these structures break down, leaving you with a grainy pile of watery egg. And there are times when, however much you whisk, the magic transformation from yellow gloop to white mousse never happens. But there are a few simple ways to (almost) guarantee yourself glossy peaks.

The first is to use a clean bowl. Any greasy residue will bind to the proteins, stopping them bonding with each other. The simplest way to avoid this is to run the cut side of half a lemon over your bowl. The acid lifts any residual grease. Using eggs at room temperature also helps the structures form.

Next, keep a close eye on your egg. As you whisk, you will go through three phases – soft peaks that melt away when you remove the whisk, firm peaks that hold their shape and then stiff peaks, which hold their shape both in the bowl and on the whisk.

Resist the urge to keep going beyond this point. The foam is fragile, and if you take it too far, the bonds between the protein strands will begin to break again, causing the structure to collapse and the water to leak out. This will also happen if you leave the foam to stand in the bowl for too long.

Accepted wisdom has it that a copper bowl can boost your chances of perfect peaks. To test this, Harold McGee and his colleagues got whisking back in 1984. They it took longer to whip up the egg whites in the copper bowl, but once the job was done, the egg whites were much more stable. It seems tiny quantities of copper from the bowl react with the proteins in egg whites, forming a combination that is more robust.

Stiff peaks achieved, gently fold in the other ingredients. With wet hands, roll into 20-22 evenly sized balls and place on a greased baking sheet lined with parchment paper. Bake for 18-20 minutes at 160°C (320°F) or until just firm to the touch. These harden up when out of the oven, so beware of over-baking. Roll in icing sugar when warm, and again when cool. They are delicious hot or cold.

Catherine de Lange is the editor of Â鶹´«Ã½ and an avid baker

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