Preheat your oven to 180°C/Fan 160°C/Gas 4. Trim the roots and top 3cm off the leek, then halve it, rinse out any grit and finely slice it. Peel and finely chop the onion. Set a medium pan on a medium heat and add ½ tbsp olive oil and the chopped veg. Season with a pinch of salt and pepper and fry, stirring often, for 5-6 mins till the veg are glossy.

While the veg fry, peel and grate or crush the garlic. Separate the parsley stalks and leaves. Set the leaves to one side and finely chop the stalks.

When the veg are glossy, stir in the garlic, parsley stalks and 1 tsp dried oregano. Cook, stirring, for 1 min, then tip in the olives and pour in the chopped tomatoes. Quarter-fill the tin with around 100ml cold water and stir it into the sauce. Pop a lid on the pan, bring to the boil and then simmer for 5 mins.

While the sauce simmers, fill and boil your kettle. Pop the white fish pie mix into an ovenproof dish, or divide it between 2 small ovenproof dishes. Taste the sauce and add a pinch more salt or pepper if you think it needs it. Spoon the sauce over the fish to cover it, then slide the dishes into the oven to bake for 15 mins. The sauce should be bubbling and the fish cooked through – it will be opaque and flake easily when pressed with a fork.

While the fish bakes, fill and boil your kettle. Tip the bulgar wheat into a heatproof bowl. Pour over 150ml hot water from the kettle. Stir with a fork, cover the bowl with a plate and set aside to soak for 15 mins. The bulgar wheat will absorb the water and become tender.

Drain any remaining water off the bulgar wheat if needed, and divide it between a couple of bowls. Serve the Greek baked fish, with the bulgar on the side, garnished with parsley leaves.