8 tablespoons soy sauce, divided
3 tablespoons sugar
3 large red onions, peeled, halved, and sliced from root to tip
3/4 cup dry white wine or vermouth
2 teaspoons plus 1 tablespoon coarsely chopped thyme leaves (or another herb of your choice, such as oregano), divided
1 1/2 tablespoons dark brown sugar
3 tablespoons organic red balsamic vinegar or red wine vinegar
3/4 cup panko bread crumbs, fresh bread crumbs, or a gluten-free alternative
1/4 cup chopped parsley
3 tablespoons melted butter
1. Cut the fish into 8 equal portions. Mix 6 tablespoons soy sauce and sugar in a resealable plastic bag and add the fillets. Seal the bag and turn it several times to evenly distribute the marinade; refrigerate for at least 4 hours (24 hours maximum).
2. Meanwhile, make the braised red onions: Cook the bacon in a large saucepan until it renders and begins to crisp. (Note: If you use salmon bacon, it will cook in 3 to 5 minutes, and won’t render much, if any, fat. Cook only until just done, not until it crisps.) Pour off half the fat (from pork bacon).
3. Add the red onions to the pan along with the wine, 2 tablespoons soy sauce, 2 teaspoons thyme, brown sugar and vinegar. Cook over medium heat, stirring occasionally, until all the liquid boils away and the onions are tender, about 15 minutes. The onions can be refrigerated until you are ready to bake the fish.
4. Toss the panko or bread crumbs with the parsley, 1 tablespoon thyme and melted butter in a mixing bowl.
5. When ready to assemble, preheat the oven to 350ºF.
6. Reheat the braised onions in a saucepan and spread them out in a large shallow baking dish. Lift the fish fillets from the marinade and arrange them on top of the onions, skin side down.
7. Top each fillet with an even coating of the crust mixture, gently patting it on with your fingertips. Bake for 25 to 30 minutes, or just until the fish flakes apart slightly when nudged with your finger and the interior is no longer translucent.
8. Turn the broiler to high and broil until the crust is golden brown. Remove from heat and let stand 5 minutes. Serve with mashed or roasted winter squash, or braised winter kale.