Beef sirloin, trimmed, sliced thinly • Fish sauce, plus 1 tbsp extra • Lemongrass, finely chopped • Kecap manis • Garlic, crushed • Castor sugar, plus 1 tsp extra • Peanut oil • Eshalots, thinly sliced • Red chillies, thinly sliced • Snow peas, trimmed • Limes, juice, plus extra to serve • Coriander leaves, to serve •