2. Add the tomatoes and mash down with a potato masher. Stir in the cumin and chilli powder, then bring to a simmer and cook for about 5 minutes until the tomatoes begin to disintegrate into a sauce.

3. Drain and rinse the kidney beans. Add most of them to the pan and mash with the potato masher. Stir in the rest of the beans and cook for at least 5 minutes to mingle the flavours. The longer it cooks, the better it gets (you'll need to add some water if you cook it for a long time).

4. Serve hot with flour tortillas, hot or cold with tortilla chips, and cold as a sandwich filling.

Serve with corn tortilla chips at a party, or with wheat tortillas and salsa for an informal (ie messy) supper. Or use as a sandwich filling. To use it as a dip rather than a side dish, you could whizz it all up with a blender, rather than mashing it, to give a smoother texture, and optionally stir in one chopped green chilli and two chopped fresh tomatoes after pureeing.