Cut butternut squash into about 1 inch (2 cm) even sized cubes.
Heat a large pot or Dutch oven over medium heat.
When hot add olive oil and once oil is hot add in onions and leeks.
Add in squash, ginger and chicken stock and bring to a simmer, cooking until the squash is tender (about 15 minutes or so).
Pour off most of the stock and reserve.
Once pureed, add contents back to pot, and add in the chicken stock until the desired consistency is attained.
Stir well and add in nutmeg, salt, and pepper to taste.