Fill your kettle and boil it. Trim the roots and top 3cm off the leek. Rinse out any grit then slice the leek into thin rounds. Peel the onions and thickly slice them. Scrub the carrots and dice them into small pieces (no need to peel them). Roughly chop the mushrooms.

Warm 2 tbsp oil in a large pan on a medium heat. Add the onion, leek, carrot and mushrooms. Season with a pinch of salt and pepper and fry for 12-15 mins, stirring now and then, till the veg soften.

Meanwhile, if you’re using the chilli, finely chop it (you can scrape out the seeds and white pith if you prefer less heat). When the veg have softened, add the chilli. Stir in 2 tsp garam masala and 1 tsp turmeric. Fry for 2 mins, stirring, till aromatic.

Pour 1.25 ltr boiling water into the pan. Drain and rinse the aduki beans and add them to the pan. Tip in the lentils and crumble in the stock cube. Bring the dal up to a boil, then pop a lid on the pan, turn the heat down and simmer for 30 mins. Stir the pan every so often, and if it gets too dry too quickly, add a splash more water and turn the heat down a little more.

While the dal cooks, trim the thick cores off the kale and shred the leaves. Stir the kale into the dal and continue to simmer for 5 mins, without the lid on the pan – this helps keep the kale green.

Squeeze the juice from half the lemon into the dal. Taste and add more salt, pepper or lemon juice if you think it needs it. Ladle the dal into warm bowls and serve.