Whiz the carrots, shallot and ginger in a blender or food processor until finely chopped. Scrape down the sides, then add the miso, vinegar and sesame oil. While the machine is running, slowly drizzle in the grape seed oil and the water.

Trim and chop lettuce into small wedges. Arrange on a platter. Scatter onion and avocado on top. If you'd like, sprinkle some flaky sea salt and black pepper over the salad at this point. Dollop with plenty of dressing and serve with remaining dressing on the side. Optionally, add a few strips of purple and yellow carrot on top that had been cut with a julienne peeler, plus some snipped chives. Toasted black and white sesame seeds would also make a pretty garnish.