Heat the oven to 220° Celsius.

First pickle your onions by mixing them with the lime juice in a small bowl with a squeeze of honey or agave and a pinch of salt. Set aside.

In a big oven-proof saucepan, heat the olive oil over a medium-high heat. Fry the garlic until lightly golden, about 1 minute. Stir in the tomato paste, paprika, ancho and cumin (be careful of splattering), and fry for 30 seconds, reducing the heat as needed to prevent the garlic from burning.

Add the beans, with their bean stock and generous pinches of salt and pepper, you may need to add a bit more water or stock here, you want it to be a molten porridge-like consistency. Simmer on a low heat for 8-10 minutes until you achieve this.

Sprinkle the cheese evenly over the top then bake until the cheese has melted, 5 to 10 minutes.

While the beans are cooking, put all of the herby sour cream ingredients into a food processor (coriander stalks and all), pour the lime juice from the red onions into it too, then whizz until smooth. Season to taste.

When the beans are browned, leave to sit for a few minutes before serving into bowls, dolloped with the sour cream and pickled onions.