Spray 4- to 5-quart slow cooker with cooking spray. Add all ingredients except whipping cream.
Cover; cook on High heat setting 4 to 5 hours.
Pour half of the squash mixture into blender. Cool 5 minutes. Cover; blend until smooth. Pour into 8-cup measuring cup or large heatproof bowl. Repeat with remaining squash mixture. Return squash mixture to slow cooker. Stir in whipping cream.
Cover; cook on High heat setting about 5 minutes or until heated through.