Remove the skin from the salmon filet and cut it into bite-sized chunks. Set aside the skin for broth.

In a large soup pot, melt 2 tablespoons of unsalted butter over medium heat. Add sliced leeks and sauté for 10 minutes until softened.

In a separate saucepan, combine the reserved salmon skin with 5 cups of water and simmer for 10 minutes. Strain into the pot with leeks.

Add diced russet potatoes and sliced carrots to the pot, stir in half of the fresh dill, bring to a boil, and then let simmer for 10 minutes.

Gently stir in the salmon chunks, 1 cup of heavy cream, and a pinch of allspice. Simmer on low heat for 3-5 minutes until salmon is cooked.

Add the remaining fresh dill and adjust seasoning with salt and pepper as needed before serving.