Mohamed Said peeked behind the curtains and explains on his blog how Laravel Valet works behind the scenes.

The idea behind Valet is that it configures PHP's built-in web server to always run in the background when the operating system starts, then it proxies all requests to a given domain to point to your localhost 127.0.0.1

http://themsaid.github.io/magic-behind-laravel-valet-20160506/

If you want to keep Homestead around for some projects, know that your can also use dnsmasq to point an entire domain to your Homestead installation.