Chilled Bacalao Soup with Celery Leaves, Potato Pancakes, and Hyssop “Oeufs à la Neige”

I ate a lot of cod when I was growing up, both fresh (cabillaud) and salted (morue in French but more commonly referred to as bacalao). We would make brandades, cooked in milk or cream, or sometimes treat the cod like a schnitzel. Here I wanted to use salt cod to make a light, refreshing, cold, creamy soup. Part of the fish needs to be blended thoroughly, so a high-speed blender is required here. One of my favorite parts of this is the garnish for the soup, oeufs à la neige