In a large pot, heat the sesame oil over medium heat. Add the chopped shallots and garlic, sautéing until fragrant and translucent, about 3-4 minutes.
Pour in the low-sodium chicken or vegetable broth, followed by the reduced-sodium soy sauce. Stir to combine, and bring to a gentle simmer.
Add the shelled edamame and cook for about 5-7 minutes if using fresh, or 3-4 minutes if using frozen.
Next, add the baby spinach and stir into the soup, letting it wilt for about 2 minutes.
Using a blender or immersion blender, carefully puree the soup until smooth and silky.
Taste the soup and adjust seasoning as needed with salt or freshly cracked black pepper.
Ladle the soup into bowls and top with sliced green onions and a dollop of crème fraîche or light sour cream.
