In a bowl, whisk together the tahini, Dijon mustard, garlic, lemon juice, Worcestershire sauce, and capers.

Slowly add water while whisking to thin the mixture to a creamy consistency.

Gradually drizzle in the olive oil while continuing to whisk until the dressing becomes smooth.

Stir in the Parmesan cheese if using, and season with salt and black pepper to taste.

Serve immediately or store in the refrigerator.