Creme Fraiche: Combine 1 cup whipping cream and 2 tablespoons buttermilk in a glass container. Cover and let stand at room temperature (about 70°F) from 8 to 24 hours, or until very thick. Stir well before covering and refrigerate up to 10 days.

Pat the trout fillets dry with paper towels then dust with salt-seasoned flour. Heat the olive oil in a large pan to medium-high, add trout and saute for a couple of minutes per side. Remove from pan and keep warm. Add ¼ C olive oil to pan with scallions and ginger just long enough to wilt greens, appx. 15 seconds. Remove from heat and transfer the scallion-ginger mix into a bowl. Add the remaining ingredients and toss. Blend 4 T of mixture into the crème fraiche and spread the remainder over the fillets. Serve with the sliced cabbage dressed with lime-cilantro vinaigrette.