In blender or food processor, combine oil, miso, lemon juice, garlic and ginger.
Blend until well combined.
Add tahini, maple syrup and 1 cup water.
With machine running, gradually add another 1 cup water and blend until mixture is smooth and creamy, scraping down sides of container as necessary with a rubber spatula to ensure no large clumps of tahini or miso are left unblended.
Be patient and resist the temptation to add more liquid; otherwise the final product will be too runny.
Stir in dulse flakes if desired.
Store in an airtight container in the refrigerator up to 4 days.
Before using, bring to room temperature, then whisk to regain its smooth texture.