Add the remaining can of beans, the tomatoes, courgettes, paprika and 5 tbsp water. Cover and very gently simmer for 10 mins until thickened and pulpy, stirring occasionally. Season to taste with lime juice, salt and pepper, then stir in the coriander. Warm the flour tortillas in a dry frying pan, then lay out with the chilli beans, shredded lettuce, sliced cucumber and soured cream dip. Ask everyone to help themselves: fill, roll and eat!