Heat wok over high heat, add oil, garlic, ginger, fish sauce and mince. Cook until mince is caramelised and brown. Remove from heat.
Return wok to the heat, add brown sugar and 40 mls water. Cook for 5 minutes or until sugar dissolves and becomes a dark caramel colour.
Add beef mince and cashews and cook, stirring constantly to prevent catching. Continue to cook until the beef is cooked through, sticky and coated thoroughly in the caramel. Add sugar snap peas, broccolini, herbs (reserving some for garnish) and top with cashews. Taste and adjust seasoning with lime juice and zest.
Place noodles on plate and top with beef mixture. Scatter with reserved herbs and serve immediately.
