1Heat a drizzle of olive oil in a frying pan over medium heat. Once hot, add the garlic and chili and cook for a minute or so, just to soften.
2Add the harissa paste and cook for a further minute, stirring constantly, until it releases its fragrance.
3Pour the chopped tomatoes into the pan and season with a pinch of salt and pepper. Bring everything to a simmer and cook for 5-6 minutes, stirring frequently, until the tomatoes have reduced slightly.
4Add both tins of butter beans, and their liquid, into the pan. Stir well then bring back to a simmer.
5Cook for 10-15 minutes, or until the liquid has reduced into a silky sauce.
6Stir through the vinegar, then taste and adjust the seasoning, adding more salt, black pepper or vinegar, if needed.
7Pour the butter beans into a bowl and serve topped with a few spoonful of yoghurt, extra oil from the harissa jar, a sprinkle of fresh dill and lots of fresh crusty bread.