Metacognition is essential for adaptability in complex environments but remains underexplored in Human-Computer Interaction (HCI). This paper leverages Sociotechnical GOMS (SGOMS) to model metacognitive processes like task switching, re-planning, and strategy adjustment. By introducing flexible “Planning Units” and integrating both reactive and deliberate metacognition, SGOMS addresses the limitations of traditional models. The proposed meta-HCI interface empowers users to simulate tasks and develop adaptive strategies, enhancing performance and resilience in dynamic settings.