Bundling JavaScript resources for an MVC app
The best practice moved from using dotNet code for bundling, to use tools for this.

The most popular and best practised tools are:


gulp
grunt


Both are tools that work on top of nodejs, an easy to install app.

Use either of these tools to minify and bundle your js and css and reference to result file.

You can make the tooling run on build events of your project to always have it bundled

But, best practise here is to use development files in development (to  keep yourdev cycle a short as possible). And in production use the bundled and minified version.