2) Meanwhile, cook the pasta according to the packet directions and drain. Remove the aubergine to a large nonmetallic bowl. Add the pasta and stir in half the feta while the pasta and aubergine are still warm. Set aside to cool while preparing the other ingredients.
3) Add in the rest of the ingredients, except the cos leaves, and gently stir to combine, adding the remaining feta cheese last. Season to taste with salt and pepper. Chill for 1 hour and serve on a bed of cos leaves on a large platter.