Blend all the ingredients except the oil in a food processor for 10-15 seconds, or until well combined. While the motor is running, pour the oil into the food processor very slowly until the well combined and the mixture is thick and glossy.
Season, to taste, with salt and freshly ground black pepper.
You can make this recipe with a whisk instead of in a food processor. You can also play around with the recipe and add lemon or lime zest for a citrus mayo or garlic to make a garlic mayo.