1/2 cup soy sauce
1/2 cup sake or dry sherry
2 garlic cloves, minced or pressed
1 inch piece of ginger, cut into thin rounds
3 tbsp brown sugar, packed
1 lb chicken or firm fish fillets (salmon, mahimahi, or sea bass), rinsed and patted dry
3 quarts water
1/4 tsp salt
4 oz. fresh spinach, rinsed and drained
2 garlic cloves
8 oz. soba noodles (or whole wheat spaghetti if that's what you have)
2 tbsp rice vinegar
1/2 cup orange juice
2 tsp dark sesame oil
In a small nonreactive saucepan, combine all of the teriyaki marinade ingredients. Bring them to a boil, then lower the heat and simmer for 5 minutes. Transfer marinade to a nonreactive baking pan and refrigerate to cool quickly. Strain the cooled marinade into a measuring cup and discard any solids.
Place the fish in the same baking pan, pour on 1/3 cup of the marinade, and refrigerate it while you prepare the remaining ingredients or up to 2 hours. In a large covered pot, bring the water and salt to a boil. Meanwhile, remove any large stems from the spinach, cut or tear into bite-sized pieces, and set aside in a large serving dish. Peel and grate the carrots, thinly slice the scallions on a severe diagonal, and mince the garlic.
Preheat the grill or the oven (400 degrees).
When the water boils, ease in the soba noodles and cook for about 5 minutes, until al dente. Drain in a colander, rinse with cold water, drain again, and set aside in a shallow bowl. Whisk together the minced garlic, rice vinegar, orange juice, sesame oil, and 2 tbsp of the remaining marinade. Pour over the cooked soba noodles and gently toss.
Remove the fish or chicken from the marinade. If fish, broil or grill on each side for 4-5 minutes per inch of thickness. If chicken, cook for about 10 -15 minutes. Turn the protein, no matter which, halfway through and baste with the marinade.
For a flashy presentation, mound the soba noodles in the center of the spinach, sprinkle the carrots around the edge of the bowl, place the protein in the center, and sprinkle with scallions. Serve immediately.