Preheat the oven to 160°C/gas mark 3. To make the tart base, place the almonds, dukkah, butter, black pepper, egg and food colouring in a food processor and process, scraping down the sides occasionally, for 3-4 minutes or until the mixture is fine and comes together. Press into a lightly greased 22cm loose-based fluted tart tin and refrigerate for 20 minutes.
Prick the base with a fork. Place on a large oven tray and cook for 15 minutes or until lightly golden. Set aside to cool.
Preheat a griddle pan over high heat until smoking. Generously brush the leeks, onions, and aubergine slices with olive oil and place on the griddle. Chargrill until black lines form and the vegetables are soft. Remove from the heat and season well.
Place the ricotta cheese and feta in a food processor with the chilli, lemon zest, garlic and seasoning and process until smooth and creamy. Season well with salt and pepper.
Fill the cooled tart case with the whipped ricotta then arrange the chargrilled vegetables on top. Scatter with the black olives and drizzle with some extra olive oil.
If you’re on a budget, halve the filling and double up on the vegetables!