1/2 head of Savoy cabbage (about 1 1/2 pounds), finely shredded
2 tablespoons chopped fresh flat-leaf parsley
1 tablespoon ground coriander
Salt and freshly ground pepper
Six 6-ounce pieces of fresh cod fillet, about 1 1/2 inches thick
18 fresh sage leaves, 12 whole and 6 minced
6 paper-thin slices prosciutto di Parma
3 tablespoons all-purpose flour
1 cup dry white wine
Juice and finely grated zest of 1 small lemon
1 cup chicken stock or canned low-sodium broth
3 tablespoons unsalted butter
Preheat the oven to 400°. In a small saucepan, boil the carrots in lightly salted water until just tender, about 2 minutes. Drain and rinse under cold water until cool. Set aside.
In a large skillet, heat 2 tablespoons of the oil. Add the onion and sauté over high heat until lightly browned, about 2 minutes. Add the cabbage and toss to coat with oil. Reduce the heat to moderate and cook, stirring occasionally, until softened, about 5 minutes. Stir in the parsley and coriander and season with salt and pepper. Keep warm over very low heat.
Pat the cod dry and place 2 whole sage leaves on top of each piece. Wrap a slice of prosciutto around each piece of cod and secure it with a toothpick. Lightly dust the cod with flour and pepper.
Heat the remaining 1 tablespoon oil in a large nonstick skillet. Add the cod and cook over moderately high heat until browned and crisp, about 2 minutes per side. Using a spatula, transfer the fish to a small baking sheet and roast in the oven for about 8 minutes, or until cooked through.
Meanwhile, set the skillet in which the fish was seared over high heat. Add the wine, lemon juice and lemon zest and boil, scraping up any browned bits from the bottom of the pan, until only a few tablespoons remain, about 7 minutes. Add the chicken stock, butter and the reserved cooked carrots and boil until reduced by half and thickened, about 5 minutes. Add the minced sage and season with salt and pepper.
Reheat the cabbage if necessary. Bring the sauce to a boil. Mound the cabbage in the center of 6 warmed plates. Set a piece of cod on the cabbage and discard the toothpicks. Spoon the sauce over the cod and cabbage and serve.