Slice the fresh squid into 2cm rings (fresh squid is available at the fish counter in store) and season with salt and pepper. Heat 1 tbsp olive oil in a large frying pan. Add the squid and cook over a high heat for 1-2 minutes until just firm and beginning to curl. Remove and drain on kitchen paper. Place the squid in a bowl and toss with 2 tbsp olive oil and the red wine vinegar. Cover and chill for 2 hours. Cut the cucumber into batons about 3cm long. Place in a colander, sprinkle with salt and leave to drain for 15 minutes (this makes it crisper). Rinse with water and pat dry with kitchen paper. Slice the medium tomatoes fairy thickly and arrange on a plate, then season with salt and pepper. Chill the cucumber and tomatoes for 20 minutes. Halve the cherry tomatoes and finely chop the red onion. To serve, add the chopped herbs, red onion, cucumber and cherry tomatoes to the marinated squid, tossing to combine. Taste and adjust the seasoning. Arrange 4 tomato slices on each serving plate and pile the squid salad on top. Serve, garnished with flat-leaf parsley.