Which of the following ingredients is NOT part of a classic Caesar dressing?

In classic Caesar dressing, olive oil is indeed a key ingredient, providing a rich and smooth texture to the dressing. The traditional recipe typically features anchovies, which add a savory umami flavor; egg yolks, which contribute to the creaminess and help emulsify the dressing; and lemon juice or sometimes white wine vinegar, which gives acidity and brightness.

While vinegar can be part of various adaptations of Caesar dressing, the classic version primarily relies on lemon juice for its tangy flavor. Thus, if we’re strictly adhering to the classic formulation, olive oil remains a fundamental component and is essential for the dressing's characteristic flavor and consistency.