Sprinkle the salmon with some of the Cajun spice. Cut a lengthwise slit in the side of the salmon.
In a bowl, combine the goat cheese, mascarpone, Parmesan 1/2 tablespoon parsley and chives. Stuff the salmon with the cheese mixture.
Using a sharp knife or mandoline, cut 1 potato into thin slices and sprinkle with salt and pepper. Using a piece of plastic wrap, lay out half the potato slices flat and place a salmon piece in the middle. Pull the plastic up over the salmon to wrap it in the potatoes like a crust. Repeat with the remaining potatoes and salmon.
Preheat the oven to 375 degrees F.
Heat an ovenproof skillet over high heat and add the oil. Sprinkle the salmon with salt and pepper and place in the hot skillet. Cook until the potato crust is brown and crispy. Cover the skillet with foil and transfer to oven to the cook for a few more minutes to medium-well.
For the sauce, melt the butter in a saucepan and add the flour, stirring to combine. Add the chicken stock, wine, lemon juice, the remaining 1/2 tablespoon parsley and a generous pinch of Cajun seasoning. Simmer until thickened.
Pan fry the mushrooms in a little oil until golden.
Spoon some sauce on the bottom of each plate and place a salmon fillet on top. Garnish with the mushrooms.
This recipe was created by a contestant during a cooking competition. The Food Network Kitchens have not tested it for home use, therefore, we cannot make any representation as to the results.