Remove the bottom 1-2 inches of the pak choi heads. Use a small cocktail grater to finely shred garlic.
Heat a drizzle of oil in a large pan on medium/high heat. While that's heating up, bring a cup of water to a boil (I used a kettle).
Place your pak choi leaves into the pan of hot oil in a single layer. Allow to sear for about two minutes before flipping to do the same on the other side.
While searing the leaves, stir your miso paste and garlic into one cup of the boiling water. It's best to use a heat-safe container with a spout because you'll need to pout it out after - like a glass measuring cup. Keep stirring until the miso dissolves and forms a broth.
Slowly pour the broth into the pan (take care not to splash yourself). Reduce heat and allow the pak choi to cook in the broth for about 10 minutes, until most of the liquid is gone.
Use tongs to lift pak choi from the pan and serve! I put mine over basmati rice with pan-seared seasoned tofu - it would also be wonderful complementing roasted meat or in a stir fry!