Cut the aubergines into 2.5 cm (1 in) cubes, sprinkle with salt, and leave in a colander to drain for 30 minutes to get rid of the bitter juices. Rinse and dry well on kitchen paper.
Heat half the olive oil in a large saucepan and fry the garlic until light brown. Add the tomatoes and simmer for at least 40 minutes until very thick.
In a separate large pan heat the rest of the o