Slice all vegetables: potatoes, carrots, onions, and celery. Pat salmon fillets dry and cut into bite-sized chunks. If using frozen, allow to thaw completely.

In a large pot, heat butter or olive oil and sauté chopped onions until soft and fragrant.

Add sliced carrots and chopped celery, cooking for a few minutes to enhance sweetness.

Pour in the fish or chicken stock and bring to a gentle boil. Add cubed potatoes and cook until fork-tender for 15-20 minutes.

Gently add salmon chunks to the pot, reduce heat to a simmer and cook for about 8-10 minutes until opaque and flaky.

Stir in heavy cream if desired; add fresh dill, salt, pepper, and a squeeze of lemon juice. Mix well.

Ladle soup into bowls, garnish with additional dill or parsley, and serve hot with crusty bread.