Once sliced, the aubergines are to be sprinkled with coarse salt, placed under a weight and left for the juices to run out. Sautè the chopped onion, the crushed garlic ad a few basil leaves in 4-5 tablespoons of oil in a saucepan. Toss in the tomatoes, roughly chopped, with a pinch of salt and reduce it all gently (15-20 minutes). Rinse the aubergine, dab dry and brown with olive oil in a frying pan. Boil the spaghetti in salted water, drain al dente and stir into the tomato souce, dredging with grated seasoned ricotta cheese. Add the aubergine, diced finely, a couple of sliced basil leaves and another liberal sprinkling of cheese.