Add all the ingredients to a small food processor and blitz until the perilla leaves are finely chopped and evenly distributed.
If you are making it without a food processor, finely chop the perilla leaves (as small as possible) by hand and then add them to a bowl with the rest of the ingredients. Whisk vigorously until well combined.
Drizzle over your favorite salad, meat or tofu. Enjoy!
Notes
Dry every leaf before it goes in: Wet leaves stick to the wall of the processor, so half come out shredded and half whole. Running the machine longer to fix that is what dulls the green.Short bursts, not a long spin: The heat and the air whipped in by a long spin turn cut shiso brown and push it toward bitter. The green you lose that way does not come back.Grate the garlic, never a whole clove: A few seconds of pulsing will not break a clove down, so you get raw chunks in some spoonfuls and none in the rest. Grated, or from the tube, it spreads through the whole jar.No shiso? Reach for Korean perilla: Korean perilla (kkaennip) is the closest stand-in, stacked near the lettuce at Korean grocers. It is bigger and more peppery, so use about three-quarters as much.