Substitute fresh or frozen cranberries, for the vattlingon. Or use half-ripe huckleberries, gooseberries, currants, blueberries or even blackberries, mulberries or raspberries. The point is slightly sweet and very tart. No spruce tips? Use lemon juice and about 1 tablespoon fresh chopped rosemary.
Salt the salmon fillets well and set them out at room temperature for 10 minutes.
Heat 3 tablespoons butter over medium-high heat in a saute pan large enough to fit all the salmon pieces. Pat the salmon dry with paper towels and lay skin side down (even if there is no longer any skin on the fish) into the hot butter. Let this sizzle like you'd sizzle bacon; the sound should be about the same. Let the fish cook for 2 minutes undisturbed.
Now use a spoon to baste the fish all over. This will cook it perfectly, leaving the center a nice medium. Keep basting for at least 90 seconds, and up to 3 minutes if you have a very thick piece of fish. For a typical piece of king salmon, 2 minutes is about right. Leave the salmon cooking for 1 to 2 more minutes, until the skin side is very crispy. Move the salmon to a cutting board to rest, skin side up.
Add the remaining tablespoon of butter and the peas. Cook for 1 minute. Add the cranberries and cook for 1 more minute. Toss to combine, turn off the heat and add the spruce tips. Put a piece of salmon on everyone's plate, pour over the pea-cranberry mixture and grind a little black pepper over it all. Serve at once.
Serve this with crusty bread or some sort of potato; roasted fingerling potatoes would be my choice.