Put the aubergine slices in a large bowl and drizzle in 2 tbsp of the oil, season and toss well. Heat a large non-stick frying pan over a high heat and cook the aubergine slices, in batches, for 1 min on each side until charred and softening, then set aside on a plate. Heat the remaining oil in the frying pan and tip in the onion with a pinch of salt. Cook gently for 15 mins until softened, then add the garlic, oregano, cinnamon and cumin, and fry for a minute. Add the tomato purée and cook for another minute. Tip in the tomatoes and green lentils along with half a can of water, season and simmer for 15 mins until thickened.

Fill a large saucepan with lightly salted boiling water and cook the potato slices for 7 mins. Drain well. Heat the oven to 200C/180C fan/gas 6. In a 25cm x 30cm baking dish, start by adding a third of the tomato sauce, topped with a third of the aubergine slices and a third of the potato slices. Repeat twice more.

For the white sauce, heat the oil in a saucepan over a medium heat, then tip in the flour and cook, stirring, for a minute. Gradually add the plant cream, a little at a time, whisking well between each addition. Season well and grate in some nutmeg to taste. Continue whisking until the mixture has come to a simmer and has thickened slightly, then pour straight over the moussaka. Bake for 30 mins until bubbling, then grill for 5 mins to brown the top.