Preheat your oven to 200°C/180°C/Gas 6. Scrub the potatoes (no need to peel) then chop them into 2-3cm-thick chunks. Tumble on to a large baking tray (or 2 medium baking trays) and drizzle over 2 tbsp oil. Season with plenty of salt and pepper and toss to coat. Slide into the oven to roast for 30 mins.

Meanwhile, add 1 tbsp mild curry powder and 2 tsp each turmeric and mustard seeds to a small bowl. Peel the garlic and ginger and grate them into the bowl. Halve the chilli, if you're using it, and flick out the seeds for less heat if you prefer. Finely chop the chilli and add it to the bowl. Zest and juice in the lemon, add 1 tbsp oil and mix together.

Cut the tomatoes into 6-8 wedges each. Peel the onions and slice them into wedges to match.

Take the potatoes out of the oven. Add the tomatoes and onions to the tray(s) and pour over the spice mix. Toss to coat the veg, and slide back into the oven for 30 mins.

Fill and boil your kettle. Pop the spinach into a large colander or sieve set in your sink or oven a large bowl. Pour over the hot water from the kettle to slightly wilt it. Leave to cool, then squeeze out as much water as possible. Finely chop the wild garlic leaves.

When the veg have cooked for 1 hr in total, add the wilted spinach and wild garlic to the tray and stir them through. Slide the tray back into the oven for 8-10 mins – the potatoes will be golden and crisp and the spinach a little dark. Heap the saag aloo onto warm plates and serve.