Put diced ginger in a saucepan and cover with water. Bring to a boil and
simmer for 15 minutes. Drain and repeat two times. Drain thoroughly and puree
ginger in a food processor until smooth and paste like; set aside.
Combine wine and shallots in a heavy saucepan and bring to a boil. Simmer
until only 1/2 cup wine remains. Add margarine, a little at a time, stirring
constantly. Add salt, mix well, and cover to keep warm.
Remove skin from salmon and remove any little vertical bones with tweezers;
cut into 4 equal portions. Spread a thin layer of the ginger puree on top of
each portion and sprinkle evenly with cracked peppercorns.
Heat oil in a skillet large enough for all 4 portions of salmon. When skillet
is very hot, sauté the salmon, ginger-side down, for 2 minutes. Turn fish and
sear other side just to seal; do not overcook. Remove fish from pan and place
on paper towel, ginger-side up.
To serve, spoon 2 tablespoons of the red wine sauce on each of four plates
and top with the salmon.