Potato has to be one of life's great comfort foods. And while I rail about the result versus the time and planning taken to bake a jacket potato to golden crunchy skin and a fluffy inside, there's no denying that slathered in butter, salt, pepper and melting Cheddar cheese, there's not much to rival it in the crawling under the duvet of food stakes.There are so many things you can do with the potato as we know, but here, because it's such a great absorber of flavour -think of the roast potatoes sucking up the juices from the meat at the end of Sunday lunch- I've used it in a curry. This goes a little beyond the quick spinach and potato saag aloo in that the spice mix is a lot more involved, it's a little saucier and the addition of tomatoes gives it a tangy and sweet richness.It's a dish I happily have on its own, but equally will go fantastically well as a side dish for a slow-roast spicy marinated lamb dish if you want a more exciting Sunday. It also makes a great dosa filling, and the chilli in this will certainly make for a more exciting breakfast. Perhaps a little too exciting, but it will certainly wake you up. And possibly ruin the day if you feed it to the children instead of egg on toast or porridge.Make the spice mix in advance and keep it in an airtight jar, then it's a matter of moments to put the dish together and leave it to simmer away for about 25 minutes to cook and thicken.IngredientsFor the spice mix:I used a combination of the following in fairly equal quantities, but you can adjust if you prefer it to have more or less heat, more aniseedy flavour and so on.SaltChilli powderGround turmericBlack mustard seedMango powderCardamonClovesFenugreek seedCuminCoriander seedFennel seedNigella seedCitric acidGarlic powderBlack pepperFor the curry:1kg Maris Piper potatoes, cut into smallish chunks150g cherry tomatoes4tbsp spice mixA few handfuls of spinachFresh coriander and sliced green chilli to serveMethodBlitz the ingredients for the spice mix into a powder. After you've blitzed it all, add some whole coriander, cumin, fennel and nigella seeds which give the finished dish an extra element of flavour.Put the potatoes, four tablespoons of spice mix and tomatoes in a large saucepan and just cover with water. Bring to the boil and cook until the potatoes are soft and the water has reduced by about half.Mash some of the potato into the liquid to thicken it and add the spinach.Stir well until the spinach has wilted, check the seasoning, add some coriander leaves and green chilli and serve. Easy.