Add the miso and rice vinegar to a jar for which you have a lid (or a bowl). Whisk until mostly smooth and there are no large miso clumps.
If using a jar to combine: add the garlic, ginger, maple syrup or agave, mustard, soy sauce, and both types of oil. Seal the jar with its lid and shake vigorously until the mixture is smooth and slightly creamy.
If using a bowl to combine: add the garlic, ginger, maple syrup or agave, mustard, and soy sauce and whisk well to combine. Combine both types of oil in a measuring cup or glass, then stream into the other ingredients, whisking as you go to emulsify. See Note
Taste for seasonings, adding more soy sauce (or salt) for salty savoriness, more maple syrup for sweetness, more mustard for creamy tang, or more sesame oil for richness.
Store leftovers in the fridge in a sealed jar for up to 5 days.
