It looks like everything is installed into node.js okay:
iMac-Home:myapp1 franceswarburton$ npm ls --depth=0
twitch-auth-sample@1.0.0 /Users/franceswarburton/myapp1
├── express@4.16.2
├── express-session@1.15.6
├── handlebars@4.0.11
├── passport@0.3.2
├── passport-oauth@1.0.0
└── request@2.83.0