You will have to decide how many this serves. It could be for 4, as a starter, or a main course for two with salad and bread. Or simply make more if you are serving more people. You’ll want more, I know that.
Tomato Sauce 2 Tbsp extra virgin olive oil 2 cloves garlic, peeled and finely chopped 1 tsp finely chopped rosemary Pinch of chilli flakes (optional) 400g (14 oz) can Italian tomatoes in juice 1 Tbsp tomato concentrate (UK tomato purée) Salt 1 medium eggplant (aubergine), sliced not too thick Olive oil 200g small balls mozzarella ¼ cup freshly grated parmesan cheese Finely grated zest 1 lemon 6 Kalamata olives in oil, patted dry and sliced Baby basil leaves for scattering
1 Make the sauce first. Put the extra virgin olive oil, garlic, rosemary and chilli flakes if using in a medium saucepan. Set the pan over a gentle heat and cook for several minutes until garlic is just starting to change colour; stir from time to time. Carefully add tomatoes, then rinse the can with ¼ cup of water and add that to pan along with tomato concentrate.
2 Bring sauce to a gentle bubble, then lower heat and cook uncovered for about 25 minutes, until pulpy and slightly oily on top. Season with a few good pinches of salt.
3 Heat a ridged grill pan or sturdy frying pan over medium-high heat. Brush eggplant slices with olive oil (you will probably need to do this in batches, so just brush as many as will fit in the pan without overlapping). Cook on both sides until a good golden brown. Transfer to a plate as they are done and season with salt. Cook remaining eggplant.
4 Drain mozzarella and pat dry balls with paper towels. Slice thickly. Sort eggplant slices into large, medium and smaller slices. Put 4 large slices in a cast iron dish, or a shallowish roasting tin and make layers of eggplant, dollop of tomato sauce and mozzarella, finishing with the smaller slices of eggplant.
5 Sprinkle with cheese then lemon zest and bake for about 15 minutes, until cheese has melted and top is browned. Scatter with basil leaves. Add olives to remaining sauce and serve on the side. Scoff up!