Biowaste represents a substantial portion of municipal solid waste, making it crucial to promote its valorization through conversion processes that transform it into valuable products. In addition, the increasing production of biowaste poses significant environmental challenges, but composting has emerged as a sustainable solution to address this issue. This study evaluates the domestic composting process of biowaste generated at the canteen of a university and its gardens. The research addresses the critical need to valorize biowaste and divert it from landfills, aligning sustainable waste management and circular economy principles. The methodology involved conducting tests with aerobic thermophilic composting in small domestic composters and pre-digestion of food waste using Bokashi fermentation. “Bokashi-treated biowaste” was subsequently tested in two applications: aerobic composting and direct soil incorporation. Temperatures in the composters reached peaks of around 45 ℃. The final composts were rich in organic matter (around 80%), and essential nutrients for soil fertility (0.6%–0.7% of P, 4%–6% of K, 4%–13% of Ca and 0.3%–0.4% of Mg). The study also measured the production of leachate and identified relevant differences among treatments. Aerobic composters generated higher volumes of leachate, while Bokashi pre-treatment reduced leachate production, thus enhancing nutrient recovery. Compost produced through Bokashi fermentation demonstrated reduced salinity and improved stability, making it particularly suitable for domestic use. This research provides valuable insights into the integration of domestic composting into sustainable waste management practices, highlighting the potential of Bokashi fermentation as an effective pre-treatment method. The findings underscore the role of innovative techniques in reducing biowaste volume, improving compost quality, and promoting resource recovery at the household level.