Good decisions fail when noise looks like signal, assumptions go unspoken, and causal stories feel true without proof. Speed, complexity, persuasive data, and AI confidence effects raise the cost of weak reasoning and unclear judgement. In this 3-hour mastery workshop, participants bring live analytical challenges and practice through a pressured case where the obvious answer is tempting. Practice centers on separating signal from noise, using base rates to reality check assumptions, thinking in systems to avoid false causality, and improving decision quality when outcomes are uncertain, sharpened through structured peer challenge. Participants leave with practical routines that make reasoning more transparent and defensible in everyday decisions, reducing risk and improving outcome confidence.