The recommended way is to use what is variously known as "port forwarding" or "tunneling". This is the most secure way to access remote applications/servers which are not exposed to public network. Digitalocean has a detailed explanation here.
Assume that MySQL is running on a server with IP remote-server-ip. Also assume that MySQL is configured to listen to the default port 3306. Briefly the steps are as follows:

1. Generate SSH public/private key pair on your computer
2. Copy your public key to remote server
3. Create a tunnel to the remote server
   

   ssh -L 3306:localhost:3306 user@remote-server-ip

   Here a secure "tunnel" is being created from port 3306 on your computer to port 3306 on the remote server.
4. Then from Prosql connections page connect to the remote MySQL server using Host as "localhost" and Port as 3306 (or whatever you used as the first number in above command)