Heat oven to 400°F. Bring a medium pot of salted water to a boil. Drop in potato slices and cook 5 minutes, drain and reserve. In a small bowl, mix together the Boursin® Cheese and the crème fraîche. Divide in half and reserve.
Tear four 16” lengths of parchment paper. In the center of each, divide and spread half the Boursin® Cheese mixture. Lay down half of the zucchini and potato in overlapping slices. Place a salmon fillet on each. Season fish with a pinch of salt and a few cracks of black pepper. Layer on the remaining zucchini and potato slices. Spread with the rest of the Boursin® and crème fraîche mixture, sprinkle with peppercorns and tablespoon each of wine.
To close each parcel, draw two edges of the paper together and fold down in 1/4” increments until nearly touching the contents of the packet. Fold under the ends and place all four on a baking sheet.
Bake in the oven for 10 minutes and serve immediately.
You can replace the salmon with tuna or a thick fillet of white fish, such as cod or haddock.