This recipe can be somewhat confusing and I am hoping to break it down to better understand. I also attached pictures as I went along to help.
1 head of garlic (remove 3 cloves, peel and slice and cut the remaining head in half crosswise)
6 scallions, trimmed (take 2 scallions and cut into 2 inch sections, take 4 scallions and thinly slice)
1 - 5 inch piece of ginger, peeled and cut into matchstick size slices
1/2 of a lemon
4 - 4 ounce filets of black cod (I used just 2 for this recipe)
1 tablespoon olive oil
2 tablespoons tamari (or soy sauce)
2 Thai chiles or 1 serrano chile, thinly sliced (I used a serrano chile because the store was out of the thai chiles. A note the serrano chile can be spicy, to reduce the spiciness remove the seeds)
1 tablespoon fresh cilantro, chopped
Combine the cut head of garlic, the cut 2 inch sections of scallions, 1 tablespoon of ginger, and 4 cups of water into a pot large enough to fit a steamer basket (I used my electric wok). Squeeze lemon on top of the water, add the lemon half to the pot and bring to a boil. Once water boils, reduce heat and simmer for 10 minutes. Transfer 1/4 cup of the liquid from pot to a small bowl; set aside for sauce. Add 2 cups hot water to pot and bring to a boil.
Set aside 1/4 cup of sliced scallions and 1 tablespoon of ginger. Line steamer basket with parchment paper (I cut mine down so that the steam holes would show on the sides). Scatter half of the sliced garlic, half of the remaining sliced scallions, and half of the remaining ginger, on top of parchment spreading evenly. Rinse fish, pat dry, place fish skin side down on top of parchment paper that had been scattered with garlic, scallion and ginger. Brush fish with oil and sprinkle with kosher salt. Scatter remaining garlic, scallions and ginger over fish. Set steamer over pot, cover and steam fish for 12 to 18 minutes until fish is flaky (timing depends on thickness of fish).
While fish is steaming, Stir the scallions and ginger that you set aside, add tamari, chile, cilantro and reserved liquid to make sauce.
Transfer fish to plate and drizzle with sauce.
Fish ready to be steamed. Sitting on top of parchment paper, scallions, ginger and garlic.
The fish finished drizzled with sauce served over rice.