Add the silken tofu, lemon juice, Dijon mustard, garlic, capers (or tamari), nutritional yeast, olive oil (if using), salt, and black pepper to a blender.
Blend until completely smooth and creamy, scraping down the sides if necessary.
Taste the dressing and adjust the seasoning by adding more salt, lemon juice, garlic, or nutritional yeast as desired
If the dressing is too thick, blend in 1 tablespoon of water at a time until you reach your preferred consistency.
Transfer the dressing to an airtight container and refrigerate for 20–30 minutes before serving. It will become thicker and the flavors will develop as it chills.