Preheat the oven to 180°C/350°F/gas 4. Put a large deep casserole pan on a medium-high heat. Peel the sweet potatoes, placing them in the pan as you go. Add 1 tablespoon of olive oil and fry for 5 minutes, turning occasionally, until starting to get golden. Push to one side, add the cumin, let it sizzle, then spoon in the jar of chipotle chilli paste and add 2 jars’ worth of water. Tip in the chopped mixed veg, finely chop and add the coriander stalks, reserving the leaves, then bake for 1 hour.
Remove from the oven and add the beans, juice and all, then the tomatoes, scrunching them in through clean hands, along with 1 tin’s worth of water. Stir well, then roast for another hour, or until the sweet potatoes are tender. Season to perfection, then – if enjoying straight away – crumble over the feta and tear over the coriander leaves, to serve. Enjoy as is, batching up extra portions to stash in the fridge or freezer for future meals.