Heat the oven to 350°F.
Bring a large pot of water to a boil and add the cabbage and vinegar; cook just until wilted (a minute or two) and drain. Heat a tablespoon of butter in a sauté pan until bubbly. Add the cabbage and cook gently, stirring frequently, until tender.
Meanwhile, julienne the apple and place the pieces in water with a squeeze of lemon until ready to use. Cook the bacon until crisp. Remove to paper towels and let cool. Crumble and reserve. Prepare the fish: Line a baking sheet with aluminum foil and place the fillets on it. Sprinkle with olive oil, salt and pepper. Cook for 5 minutes.
While the fish is cooking, make the sauce: In a saucepan, heat 2 tablespoons of butter. Add the shallots and sauté until translucent; do not let brown. Deglaze the pan with the white wine and cook until reduced by half. Off the heat, add the cold butter and stir until emulsified. Add the peppercorns.
To serve, place the trout on a bed of cabbage and top with the julienned apples. Garnish with crumbled bacon and drizzle with the pepper sauce.
