To achieve successful mine closure and restore derelict land, implementation of sustainable mine-site rehabilitation schemes aligned with circular economy principles should be prioritised using proactive strategies. To address both the need for fertile topsoils for mine-site rehabilitation and the desire to re-purpose benign mine wastes towards materials of value, an effective approach towards controlled resource management based on waste valorisation involves using the major coal ash fraction of coal waste to fabricate a soil (referred to as a technosols, FabSoil) by amending it with a suitable organic waste source. This technosol can be developed as a topsoil to remediate the degraded mine land. This study investigated the improvement of the fertility of the technosols, previously reported as FabSoil, through bioaugmentation and biostimulation. The FabSoil was fabricated from ultrafine coal tailings, inoculated with commercially available microbial inocula and amended with three different amounts of malt residue (2.5%, 5%, and 7% w/w) from a local brewery. Eragrostis tef (teff), a first-stage plant species, was grown in each of the treatments. The results indicated bioaugmentation of technosols amended with 5 wt% malt residue presents a favourable condition for the development of primary species used in site rehabilitation. This is expected to accelerate the establishment of self-sustaining fertile soils for the rehabilitation of disturbed mining areas.