1 medium yellow onion, peeled and sliced into
thin wedges (optional)
1 pound beef sirloin, thinly sliced against
the grain into bite-size pieces
1 tablespoon fish sauce
freshly ground black pepper
1
Heat the oil in a wok or nonstick skillet over high
heat, add the onion, and cook until translucent but firm, 5 to 7
minutes. Add the beef and fish sauce, season to taste with pepper,
and stir-fry until beef is cooked through, 2 to 3 minutes.