Stuffed blue corn cakes (Tlacoyos)

1. Knead the blue masa harina with the salt and enough lukewarm water to make a soft, non-sticky dough; divide into 8 balls. If you can't get blue masa harina, regular (yellow or white) is fine – only the colour will differ.

2. Mash the cooked black beans with a fork into a thick purée and salt. Flatten each ball slightly, put a spoonful of beans in the centre, close it up and shape into an elongated oval with pointed ends, about 1 cm thick.

3. Cook the tlacoyos in a hot, dry pan for 4-5 minutes per side, until cooked through and spotted brown.

4. Meanwhile, clean the nopales (cactus paddles) of spines, cut into strips and fry in a little oil for 8-10 minutes until their slimy liquid has evaporated; salt. If you have no nopales, green beans work too.

5. For the green salsa, boil the tomatillos for 5 minutes and blend with a little coriander and salt.

6. Spread the tlacoyos with green salsa, top with the nopales and serve with crumbled queso fresco (or a mix of feta and ricotta), chopped red onion and coriander.

Tip: The tlacoyo is one of the oldest street foods in Mexican markets – instead of beans you can fill it with cooked, mashed broad beans or cheese.