Angular CLI - Generate external CSS file from SASS

I have the following settings in my angular-cli

"styles": [
        "styles.css","assets/scss/app.scss"
      ],

"defaults": {
    "styleExt": "scss",
    "component": {}
  }

the above compiles all SCSS into CSS and inserts into a <style> tag in the page. How do I make the CLI generate an external CSS file, so I can <link> it?