Mayonnaise 101

• If you mix up a simple vinaigrette for your salad and shake it vigorously, the oil and vinegar will combine for a few minutes and then gradually separate. If you combine the vinegar with an egg yolk and beat in the oil gradually, emulsifiers in the egg yolk will keep the vinegar and oil together permanently. That exact technique is how mayonnaise is made from scratch. Its flavors can be altered by your choice of vinegars, or by adding flavoring ingredients.

Aioli

• Aioli is a variation on mayonnaise, originating in the Mediterranean areas of France, Spain and Italy. All three countries have their own versions. It takes its name from the presence of garlic, which is "ail" in French. In mid-range restaurants, cooks sometimes add finely minced garlic or garlic paste to a commercial mayonnaise as a substitute, but ideally it's made from scratch. Some traditional recipes use no egg, relying on the garlic's own juices -- or sometimes, breadcrumbs or mashed potatoes -- to emulsify the other ingredients. Those versions of aioli aren't as stable, and will break down if they aren't used within a few hours.

Smoked Red Pepper

• Hot or sweet red peppers are versatile ingredients in many dishes, and they can also be treated as a spice. For example, paprika is made by drying thin-skinned pimento peppers, then grinding the dried flesh into a fine powder. Mexican cooking is rich in smoked peppers of all kinds, and both Spain and Hungary -- the world's two foremost paprika producers -- have smoked versions of their sweet and hot paprika. The best smoked Spanish paprika, called "pimenton de la vera," is officially protected under European law. That term can only be used for specific peppers, grown in a designated region and cured through a specific process.

Cilantro

• Cilantro, also known as fresh coriander or Chinese parsley, is a signature ingredient in dishes from Mexico, India, Central Asia, Thailand and Vietnam. It's closely related to parsley and caraway, and has a distinctively fresh, citrusy flavor. It dries poorly, so it's usually chopped or juiced immediately before it's included in a sauce or recipe.

The Combination

• A smoked red pepper cilantro aioli, then, is a garlicy mayonnaise with the rich, smoky flavors of smoked paprika or smoked hot peppers, brightened by the addition of cilantro. It could be used to lend Southwestern flavors to a simple sandwich, or as a condiment in the cavity of a ripened avocado. Cooks might also use it as the binding ingredient in a flavorful chicken salad, in spicy devilled eggs, or as a dip with a tray of cut raw vegetables.