20 mins (plus resting)
For the beef heart
- ½ beef heart (500g)
- ½ tsp ground cumin
- 1 heaped tsp dried oregano
For the salsa
- 200g cherry tomatoes
- 1 dried ancho chilli
- 1 tsp smoky paprika
- 1 tsp granulated sugar
- 150ml just-boiled water
To garnish and serve
- 100g red onion, peeled and very finely diced
- 60g white wine vinegar
- 25g granulated sugar
- 10-12 stems of coriander, leaves picked
- 13 x 10cm corn tortillas
Make the pickled red onions and tomato salsa first. Put the finely diced onion in a small bowl. Add a good pinch of salt, mix and leave to macerate for 15 mins. Heat the vinegar and sugar in a small saucepan, stirring until the sugar has fully dissolved, then pour this over the onions. Cover with clingfilm and leave for at least an hour, after which the onions will have turned bright pink. You could do this up to 24 hours before if you wish.
To make the tomato salsa, rehydrate the chilli by putting this in a small container and pouring approximately 150ml of just-boiled water over the top. Leave for 30 mins, then remove from the water and chop finely.
Put the chopped chilli, the water used to hydrate it, the cherry tomatoes, paprika, sugar and a pinch of salt into a small but heavy bottomed saucepan. Bring to the boil and simmer over a low-medium heat for 20-30 mins until the water has almost entirely evaporated. Squash the tomatoes a little to release excess water (but they should otherwise be intact), and boil and reduce for 5 mins more. Leave to cool – you will have a sweet, smoky, sticky salsa.
To prepare the heart, slice any hard fat and sinew from the outside (it’s quite obvious which is lean muscle and which is fat). Slice the heart to open it flat. Cut out any sinew from the middle, then slice into manageable sections. Slice each piece into 1cm-thick lengths, then these lengths into 1cm dice. Mix with 1 tbsp sunflower oil, the oregano and cumin.
It takes barely 1 min to cook the ox heart, so you may wish to cook in batches – perhaps eat half the tacos then cook again.
Put a large frying pan or wok over a very hot hob. Add 1 tbsp sunflower oil and heat until nearly smoking. Tip the diced ox heart into the pan, stir quickly to ensure the dice are thinly spread across the pan, then leave to brown without touching for 30 secs. After that time is up, stir quickly again so the raw parts of the heart now touch the pan, then leave for another 30 secs. Decant the meat from the pan into another container to rest for 1-2 mins while you get everything together.
While the heart is cooking, warm the tortillas on another frying pan over a low-medium heat.
To assemble, add a spoonful of tomato salsa to the base of each tortilla. Top with a mound of ox heart, ½ tsp pickled onions and a few coriander leaves. Eat immediately.
Image: Ed Smith