1.Place sesame seeds and garlic in a mortar and pound with a pestle until smooth. Add sambal oelek, soy sauce, caster sugar, vinegar and oil. Stir to combine.
2.Heat a barbecue or chargrill on high. Place steak in a bowl and stir through 1/4 cup of sesame mixture. Cook steak for 1-2 minutes each side or until browned and just cooked. Add steak to half of remaining dressing and toss to combine.
3.Meanwhile, cover noodles in boiling water and soak for 2-3 minutes or until just tender. Use a fork to separate. Drain rinse under cold water and drain again.
4.Combine noodles, cabbage, green onion, radish and remaining dressing in a bowl. Divide noodle mixture between serving bowls and top with beef to serve.