coat a dutch over with cooking spray

add margarine

place over medium heat until margarine melts. add onion and garlic, saute 5mins or until tender

add flour, stirring until smooth

stir in chicken broth and next 4 ingredients. bring to a boil. cover, reduce heat and simmer 45 mins or until squash is tender

let mixture cool slightly

add squash mixture to food processor

return mixture to pan, add milk. cook over medium heat until heated, stirring occasionally. do not boil.