Mix the sugar and all the ingredients up to and including the seed & nut mix in a pan, bring to the boil, stirring constantly, reduce the heat, simmer for approx. 5 mins., occasionally shaking the pan, until the seeds are slightly toasted. Transfer the seeds to a sheet of baking paper and allow to cool.
Heat the butter in a pan, sauté the shallot and squash for approx. 5 mins. Pour in the stock, bring to the boil, reduce the heat, cover and simmer for approx 20 mins., puree, season. Slice off the top and bottom of the orange, then peel all round the fruit down to the flesh. Using a sharp knife, cut out the segments between the white membranes. Press out the juice (approx. 50 ml) and add to the soup with the orange segments. Gently heat through.