Cook the cherry tomatoes in a saucepan with the chopped onion; add salt. When the tomatoes are cooked, pass them through a vegetable mill and keep the sauce warm. In the meantime, wash peel and dice the eggplant, and fry in very hot oil. Remove them with a slotted spoon and pat with absorbent kitchen roll to take away the excess oil. Toast the pine nuts in the oven until golden and brown the breadcrumbs in a little olive oil in a frying pan until crispy. Add the fried eggplant to the cherry tomato sauce and let them absorb the flavors for a few minutes.
In the meantime, cook the pasta in plenty of boiling, salted water, drain al dente and add the spaghetti to the sauce. Mix well, then add the breadcrumbs, stirring quickly.