Use leftover roasted thin-skinned potatoes for this soup. If you don't have leftovers, use this method. Wash the potatoes well and blot dry. Coat with olive oil. Roast uncovered at 425 degrees F for about 45 minutes, according to your oven and the size of the potatoes. Potatoes should be just tender in the center when pierced with a fork. Allow to cool enough to handle, then dice.
Cook the bacon until the desired crispness. Tip: I often will cook the bacon in a pan on the stovetop until it is almost as crisp as I want, then transfer it to an oven-proof plate between layers of paper towels. Bake at 300 degrees F until it is as crisp as you like. The paper towels will absorb the extra bacon fat.
Heat bacon fat or olive oil over medium heat. Add the leeks and celery and stir for 5-6 minutes or until slightly softened. Add the garlic and cook for about 1 more minute until fragrant. Pour in the broth and bring to a simmer for about 5 minutes. Stir in the diced potatoes and herbs and return to a simmer. Cook until the celery is tender, about 10 minutes.
Use stick blender to puree the soup to the chunkiness you desire. We like it fairly smooth. (If you prefer your spinach chopped fairly fine, add it to the soup before pureeing it.)
Stir in the spinach, corn, coconut milk, salt, pepper and about 1 cup of the fish. Simmer about 10 minutes or until flavors have blended. Taste and adjust the seasonings.
Ladle the soup into bowls.
Garnish with remaining salmon pieces, bacon and herbs.