how to recover a deleted AD user with mailbox

hi i have exchange 2010 sp2 mailbox server on which i have user called sam joshua. we are using Backup Exec 2012.

i'm taking regular backup of mailbox server (Full and Incremental Backup) and AD server (Full Backup). The user id has been deleted from the AD. Now what steps i need to take for restoring that user with mailbox.

should i restore User from AD backup first  and then Mailbox.

Regards

Devang