The cornflour slurry is what gives it that takeaway-style glossy sauce. Mix it with cold water first so it does not clump. | You can swap beef mince for chicken mince, turkey mince, pork mince or finely chopped steak. | Use whatever quick-cooking veg you have: broccoli, mangetout, mushrooms, courgette or frozen stir-fry veg all work. | For more heat, add chilli oil, sriracha or dried chilli flakes at the end. | Store in the fridge for up to 3 days. Reheat in a pan with a splash of water to loosen the noodles and bring the sauce back to life.