Preheat oven to 200 C/400 F
In a small bowl mix soy sauce, sesame oil, and ginger. Set aside.
In a small saute pan heat vegetable oil over medium heat. Saute shallots and shiitake mushrooms until just soft. Add the wine or stock and cook for a few minutes longer. Set aside.
Place the bok choy in the center of a large piece of baking paper. Top with half of the soy/sesame/ginger mixture and half of the garlic slices.
Place the cod on top of the bok choy.
Mix the remaining soy/sesame/ginger mixture with the shiitake/shallot mixture and place on top of the cod. Top with the remaining half of the garlic slices.
Fold the baking paper to seal. Place on top of a baking tray and bake for 20 min.
Serving suggestion: Serve over jasmine rice.
To note - when increasing the number of servings do not simply double, triple or quadruple to wine/stock in the sauté mushroom step. For one serving 1/4 cup, 2- 3 servings 1/3 cup, 4 - 6 servings 1/2 cup.