Melt butter in a sauté pan, once the butter is hot, add the shallots and the leeks and allow them to soften, about 3 minutes, then add the squash, garam masala and the salt and pepper. Cook on a medium heat until the squash begins to soften a bit, about 5 minutes, and then add 2 cups of the chicken stock and turn the heat to a medium low. Simmer for 15 minutes. Remove the soup from heat and puree in a food processor or blender until completely smooth and return to a clean sauce pot. Add the additional 1 1/2 cups of chicken stock, vermouth and heavy cream. Allow to simmer on a low heat for 5 minutes and then add the sweet marsala wine and heat on low for an additional 5 minutes.

If using the lump crab meat, place the crab in the center of the individual serving bowls.

Pour the soup into the bowls and top with a dab of crème fraiche.

For a buffet party you can serve this in individual shot classes and top with crème fraiche or in a demi tasse.