In a medium saucepan, heat sesame oil over medium heat. Add shallots and garlic and cook, stirring until lightly golden and fragrant, 1 to 2 minutes.
Add broth, soy sauce, and edamame and bring to a boil.
Cover, reduce heat to medium-low, and simmer until the edamame are tender, 15 to 20 minutes.
Add spinach and cook for 1 minute more.
Working in batches, puree the soup in a blender (use caution blending hot liquids).
Return to saucepan to keep warm.
Ladle the soup into 4 serving bowls.
Top with black pepper, scallions, and a small dollop of créme fraîche.
