1.Brush beef, both sides, with oil; cook on a heated barbecue grill plate, 5 minutes each side or until cooked as desired. Remove from heat. Cover; stand 5 minutes. Slice beef thinly.
2.Place vermicelli in a large heatproof bowl, cover with boiling water; stand until tender, drain. Cut vermicelli into random lengths into same bowl.
3.Meanwhile, make lime dressing. Blend or process ingredients until chopped finely.
4.Place beef and half the dressing in a large bowl with remaining ingredients; toss gently to combine.
5.Drizzle remaining dressing over vermicelli. Divide vermicelli among shallow serving bowls; top with beef salad.
The dressing can be made several hours ahead. The salad can be prepared leaving only the steak to cook and the vermicelli to soften.