A method for efficient file-based backups and recoveries. The method includes: receiving, to initiate a backup session, a file-system backup instruction identifying a host file-system; obtaining at least one clone logical cluster number (LCN) corresponding to a file managed by the host file-system, and a region LCN corresponding to a file region of the file; based on a determination that the region LCN matches a clone LCN of the at least one clone LCN: querying a cluster-offset tracking data structure using the region LCN to identify a cluster-offset tracking entry including the region LCN and a container offset; writing, as a session metadata record stored in backup session metadata for the backup session, file metadata describing the file and including the container offset; and transmitting, to a backup target, an information tuple including a backup session identifier generated for the backup session, and the backup session metadata.