If you need to enable SSL on Xampp whilst stilling using vhosts, follow the next few steps. It assumes that you already have vhosts enabled.

Open xampp/apache/conf/extra/httpd-vhosts.conf Around line 19 you should see

NameVirtualHost *:80

below this line add

NameVirtualHost *:443

Then add a new vhost site just like a normal one but with 443 instead on 80 and the following lines:

SSLEngine on
SSLCertificateFile conf/ssl.crt/server.crt
SSLCertificateKeyFile conf/ssl.key/server.key 

An example of this is:

<VirtualHost *:443>
    DocumentRoot "C:/xampp/htdocs/myproject/public"
    ServerName mysite.local
    ServerAlias mysite.local
	SSLEngine on
	SSLCertificateFile conf/ssl.crt/server.crt
	SSLCertificateKeyFile conf/ssl.key/server.key 
</VirtualHost>

Restart Xampp apache and everything should work fine.