If You Can't Find Niçoise Olives For Your Salad, Kalamata Are A Perfect Replacement
Originally a sandwich made with tomatoes, anchovies, and olive oil (the pan bagnat), the niçoise salad has evolved over the years to become a classic summertime salad. Although the assembly of the niçoise salad has been debated, nearly everyone will agree that olives are a critical component: according to The New Yorker, "the (more-or-less) accepted version of the salad" contains 11 ingredients, including olives; for the Cercle de la Capelina d'Or, defenders of culinary traditions from the Nice region (where the namesake salad originated), the modern niçoise salad has seven ingredients, including niçoise olives (via Times of Malta).
Similar to the salad, niçoise olives also take their name from the city of Nice, so it's not surprising that they would be the olive of choice for the niçoise salad. However, niçoise olives are not always easy to find, especially if you don't live near a major city or specialty food markets. Luckily, you can replace niçoise olives with a popular and easy-to-find cultivar — kalamata olives. With similar flavor profiles, kalamata olives are an ideal substitute when you can't find niçoise olives.
How the two olives compare
Grown in southeastern France, niçoise olives are small and dark, with a large pit and a firm texture. They have a fairly strong, though not overpowering, flavor for their size. Typically sun-dried before being brine-cured, they have a bitter, earthy, and nutty flavor, with hints of licorice and wine. Kalamata olives are the most popular Greek olive, and one of the most popular olives in the world. Grown near their namesake city of Kalamata, they're large and meaty, and known for their almond shape and deep purple color. Brine-cured and typically preserved in red wine, red wine vinegar, or olive oil, they have a rich, tangy, and somewhat fruity flavor.
A key ingredient of the Greek salad, kalamata olives also work well in a niçoise salad — in fact, many recipes will explicitly list kalamata olives as a substitute for niçoise olives. Similar in texture, both are brined cured and offer a rich, tangy, and slightly bitter flavor, though kalamata olives tend to be somewhat sweeter and fruitier than niçoise olives. Given their larger size, you won't need as many kalamata olives as you would niçoise olives. Also, kalamata olives can be much saltier, so you may want to rinse them before using them in a niçoise salad.