How to Make It
In a blender, combine all of the ingredients and season with salt. Puree the yogurt sauce until it is smooth. Transfer the sauce to a bowl and refrigerate.
In a deep skillet wide enough to fit the salmon fillets in a single layer, combine the wine, parsley, dill, peppercorns, lemon and 2 cups of water. Bring to a boil. Season the salmon fillets with salt and add them to the pot in a single layer. Cover and poach over moderately low heat until the salmon is just cooked through, about 8 minutes.
Using a slotted spoon, transfer the salmon to a work surface. Remove and discard the salmon skin. Transfer the fillets to plates and drizzle with some of the yogurt sauce. Garnish with dill and serve with potatoes.