I make a similar version.
Budget constraints often dictate portion sizes, making single-serving preparations surprisingly tricky when working with tender cuts like top sirloin steak. Cutting expensive beef down to a single portion requires careful heat management to prevent the meat from overcooking during the initial browning phase. High heat applied to thin strips creates the necessary Maillard reaction without toughening the interior fibers.
Adjusting ingredient proportions downward involves more than simple division. Dairy elements like sour cream and canned soup react differently when volumes shrink, as moisture evaporates faster in smaller pans. Adding beef broth gradually allows control over viscosity, preventing the sauce from becoming overly watery when reduced alongside sliced mushrooms. Worcestershire sauce and ketchup provide contrasting umami and acidity, balancing the heavy fat content derived from the dairy and beef.
Doubling or tripling the quantity for multiple diners necessitates a wider skillet rather than a deeper pot, ensuring the meat maintains contact with the hot surface instead of steaming in its own juices. Cook the sliced onions until translucent at medium-low heat to extract natural sugars without burning the aromatics.