Heat the olive oil in a large saucepan or flameproof casserole dish over a medium heat and cook the onions, peppers, garlic and chilli with a big pinch of salt for 10-12 mins, stirring often until the veg is softening and lightly golden around the edges.

Add the paprika, cumin, chipotle chilli paste and tomato purée, and cook for 2-3 mins until aromatic and darkened slightly. Pour in the chopped tomatoes, swilling out the can with water, then add the black beans.

Bring to the boil, then reduce the heat to a simmer. Add the red wine vinegar and sugar, and stir to combine. Continue to cook over a medium heat, uncovered, for 35 mins until reduced and thickened.

When the chilli has 20 mins left, cook the sweet potato fries following pack instructions.

Put the crispy sweet potato fries on a large platter or plate. Spoon over ladlefuls of the chilli, then crumble over the feta. Dot over the pickled onions and avocado, if using, then sprinkle over the coriander. Serve with lime wedges for squeezing over.