In a large pot, add oil over medium heat.
Add the diced onion and fennel to the oil. Sauté, stirring occasionally, for about 15-20 minutes until softened and golden brown. Let them brown a bit on the bottoms.
Stir in the salt, ras el hanout, black pepper, and fennel seeds. Cook for 1 minute.
Add the broth and the cooked squash to the pot. Stir.
Bring to a boil, then reduce the heat and simmer for about 10-15 minutes to let the flavors meld.
MEANWHILE, toast the pepitas, then set aside. (Dry frying pan on medium-low heat, stirring frequently, just until they smell toasty and the color starts to turn light brown - about 10-15 minutes)
Remove soup from the heat.
Use an immersion blender (or transfer to a stand blender in batches) to blend the soup until smooth and creamy.
Taste and stir in extra salt if needed. (Salt needs will vary depending on what broth you use)
Serve with a dollop of greek yogurt and a sprinkle of toasted pepitas.