1. Gently pull the head and tentacles away from the body and discard the entrails.
2. Cut the tentacles from the head just below the eyes. Reserve the tentacles and discard the head.
3. Remove and discard the fine, purplish-black membrane from the body.
4. Trim the side "wings" from the body and set aside.
5. Pull out the clear "backbone" (quill) from inside the body, then rinse body, tentacles and wings thoroughly and pat dry with kitchen paper.
6. Cut squid down the centre so that it will open out flat.
7. Using a sharp knife, score shallow diagonal cuts in a crisscross pattern on the inside surface, taking care not to cut right through the squid. Scoring squid makes it curl on contact with hot oil, while also allowing flavours to penetrate into the squid.
8. Cut the scored squid in half and then into four-centimetre strips.
9. Trim the reserved "wings", then cut in half.