Pfsense OpenBGPD prepending path bgp setup

[emiliano.angieri]

Hello Guys,

I'm creating a VPN with AWS following this guide:
https://www.1strategy.com/blog/2017/08/29/tutorial-using-pfsense-as-a-vpn-to-your-vpc/
I need to configure the as path prepend because I have multiple tunnel to configure and I would like to avoid any issue with asymmetric routing.

Is there any guide that explain how configure as path prepend with OpenBGPD?
Is it available in pfsense gui?
Alternatively if it is not available, how can I configure BGP Tunnel with AWS configuring AS PATH PREPEND with bgp?

Reading here seems available but I didn't understand were:
https://redmine.pfsense.org/issues/2825

Thanks in advance.
Kind Regards,