Peruvian beef heart skewers (Anticuchos de corazón)

1. Clean the beef heart thoroughly: trim off the fat, tough vessels and membranes, then cut into 3-4 cm pieces about 1.5 cm thick.

2. In a bowl, mix the ají panca paste with the red wine vinegar, crushed garlic, cumin, oregano, salt, pepper and a tablespoon of oil.

3. Turn the heart pieces in the marinade, cover and refrigerate for at least 3 hours, or even overnight; meanwhile soak wooden skewers in water for 30 minutes so they don't burn.

4. Thread 3-4 pieces onto each skewer and mix the leftover marinade with the remaining oil – you'll use it for basting.

5. Heat the grill or embers until very hot and cook the skewers for 2-3 minutes per side, basting several times; the heart should stay pink inside, as it turns chewy when overcooked.

6. Serve immediately, piping hot, with boiled potatoes, boiled corn and ají sauce, just like at the street stalls in Lima.

Tip: Beef heart is surprisingly lean and tender if you don't overcook it – if you're a little wary, start with a skewer or two and make the rest with chicken breast.