The pasta is boiled for about 10 minutes (or as it says on the box) in boiling salted water, stir from time to time so as not to stick.
Cut the onion into scales and put it to harden in olive oil.
Cut the eggplant into cubes or suitable pieces and add over the onion.
Put enough water to cover and let it boil over low heat.
When the vegetables are almost cooked, add water if necessary and tomato paste together with the spices to taste.
Let the sauce drop a little and serve with the cooked pasta.