Place eggplant in a large bowl, add 2 tsp fine sea salt, toss to coat and set aside for liquid to drain (20 minutes).
For sugo, heat oil in a frying pan over high heat, add onion and stir occasionally until starting to caramelise (3-5 minutes), then add garlic and stir until caramelised (1-2 minutes). Add fresh and canned tomato, oregano and reserved basil stalks, bring to the simmer, reduce heat to medium and stir occasionally until tender and thick (30-40 minutes). Remove stalks (discard), transfer to a blender, season to taste and blend until smooth.
Heat olive oil to 3mm deep in a frying pan, dust eggplant slices with seasoned flour, shake off excess, then fry in batches, adding more oil as necessary, until golden (2-4 minutes). Drain on absorbent paper.
Preheat oven to 180C. Spoon a little sugo into a 15cm x 25cm baking dish, top with a layer of eggplant, scatter with parmesan and basil, then repeat until all ingredients are used, finishing with a layer of sugo. Scatter with extra parmesan, bake until golden and bubbling (20-30 minutes), scatter with extra basil and serve with a bitter leaf salad.
