Peel and dice squash and boil in water until tender. Drain and mash the squash. Set aside.
Heat butter and saute garlic until fragrant but not brown. Add celery and stir cook until tender.
Stir in white wine, if available. Cook over low heat until most of the wine has evaporated.
Add mashed squash and chicken broth. Bring to a boil while stirring occasionally. Add in crab meat and stir cook for a few minutes.
Then stir in evaporated milk, sugar, salt and pepper.
Reduce heat and simmer for 5 minutes.
Add in all-purpose cream and heat through. Serve hot with a garnish of chopped parsley and nutmeg if desired.