To make the quick pickled shallots: whisk the red wine vinegar, sugar, salt and water in a small bowl until the sugar and salt dissolve. Place the sliced echalions in a bowl and pour the vinegar mixture over. Let it sit at room temperature for 1 hour.
Slice all of the courgettes lengthways on a mandoline, or with a flat vegetable peeler, into strips about 3mm thick.
Place the strips in a colander over a bowl, season with a little salt and leave to stand for 8 minutes to extract the excess water. Pat dry on kitchen paper. Meanwhile, toast the pine nuts in a dry frying pan until golden brown.
To make the dressing, pour the lemon juice into a large bowl and season with salt and pepper. Gradually whisk in the olive oil.
Pile up the courgettes on a serving platter or individual plates, evenly distributing the yellow and green vegetables and making sure you create some height. Sprinkle with the toasted pine nuts and drizzle with half of the dressing. Add a layer of the rocket leaves and drizzle them with the rest of the dressing. Finish the dish with some of the pickled shallots and a scattering of Parmesan shavings