Preheat the oven to 200° C.
Halve the squash lengthwise and remove the seeds. Cut the squash into 1-cm cubes and cut the onion into sections. Place on a baking sheet and sprinkle with 2 tablespoons of oil, some salt and the ras el hanout. Roast squash and onions for 20 minutes or until they are golden brown and cooked through.
Retain 1/4 of the squash cubes and place the rest in a frying pan. Add 1 litre of water and bring to the boil. Add the vegetable stock cube and continue to boil for a few minutes.
Puree the soup to a smooth consistency with a hand mixer. Stir in half of the coconut milk; retain the rest for later. Season the soup to taste with salt and pepper.
Dice the avocado, ladle the soup into bowls and spoon some coconut milk over the soup. Distribute the avocado cubes and roasted squash cubes over the soup. Garnish the soup with the sprouts and sesame seeds.