1. Go to Stock Management, find the meal/portion line at the location and click Edit Stock.
2. In the Stock Movement window the Type of movement is Remove Stock (the only option in this version). Enter the Quantity to remove and choose the Reason of movement from your Stock Management Justifications (e.g. Waste, Damaged, Sold). The window shows the current Stock available for reference.
3. Click Save movement. The page reloads (the movement is saved and the modal's dropdown only ever offers Remove Stock) and the line's stock and Last Stock Update update.

Each save creates a movement record (quantity, reason, who and when, stock before the movement). Adding stock is done from the Retail Menu page (Update Stock, the CSV upload) rather than here. Reasons are managed under Kitchen Settings > Stock Management Justifications (Description + Status).