My grandmother always puts cloves in onions – here’s why this French technique changes everything.

The secret to sparkling onions: why this old trick transforms any soup

There are cooking techniques that seem strange at first, until you taste them. Then, everything becomes clear. This was also the case with my grandmother’s secret: every time she prepared a soup, a broth, or a stew, she would gently press a few whole cloves into a peeled onion before adding it to the pot.

At first, I thought it was just an old habit. But when I tasted the dish—rich, deep, and subtly spiced—I understood: it wasn’t just a tradition, it was pure culinary magic. Today, I use this trick with almost every savory dish that simmers for hours, and I’ve even passed it on to my children. But why put cloves in an onion?

What is a pierced onion? The French art of seasoning.

In classic French cuisine, this method is known as “onion piqué” or “cloué.” The word “clou ” means “nail” in French, and “cloué” can be literally translated as “nailed.” This perfectly describes how the nails are driven into the onion like tiny nails.

This technique gives soups, sauces, and stews a rich, aromatic depth that is difficult to replicate otherwise. The onion acts as a carrier, slowly and evenly releasing the intense essential oils of the clove into the liquid. The result is a complex flavor profile that distinguishes an amateur dish from a professional one.

The science of taste: why do cloves and onions go well together?