Cut the egg plant in round thin slices using a mandoline or cheese slicer.
Heat a cast iron grill pan until very warm.
Meanwhile, spread out the slices of egg plant on a board and brush some olive oil on them.
Grill the slices by putting them in the grill pan without any overlap and turn each slice around 3 times (each time after some time to let them acquire a grill mark) to create a nice grill pattern. Place the grilled slices on a paper towel and salt them as soon as they're ready and before starting the next batch.
Meanwhile, shortly roast the pine nuts in another pan.
Dressing and plating
Take a big plate and place the slices in a large circle (the slices slightly overlapping) and smaller circles to fill the first circle up.
Add a bit of olive oil to the pesto and drip it over the melanzane.
Spread the roasted pine nuts over the plate.
Put a handful of rucola on the centre.
Dress with a few more drops of olive oil.
Grate some Parmigiano over it and you're ready to serve!