Place all of the dressing ingredients into a blender and blend until smooth.
Add ¼ cup water and blend until smooth. If necessary, add more water, 1 tablespoon at a time, until you have a thick but pourable consistency.
Adjust the seasoning to taste with salt and pepper.
Notes
This dressing is best eaten right away, but you can transfer it to an airtight container and it will keep in the fridge for 3 or 4 days, or it can be frozen for up to 2 months.