HEAT oil in large saucepan on medium heat. Add squash, onions and garlic; cook 5 to 10 min. or until crisp-tender, stirring occasionally. Stir in allspice; cook 1 min.

ADD chicken broth. Bring to boil; cover. Reduce heat to low; simmer 15 min. or until squash is tender. Add, in batches, to food processor; cover. Process until smooth. Return to saucepan. Cook until heated through, stirring occasionally.

LADLE soup into eight bowls. Add 1 Tbsp. sour cream to each bowl; stir gently to swirl. Serve with the crackers.