Nigerian peanut-spiced beef skewers (Suya)

1. Toast the peanuts in a dry frying pan, let them cool, then grind to a fine powder in a food processor (in short pulses, otherwise it turns into butter).

2. Mix the ground peanuts with the chilli powder, paprika, ground ginger and salt; this is the yaji spice mix.

3. Cut the beef across the grain into 3-4 mm thin slices, toss with the oil and crushed garlic, then rub in two thirds of the yaji well and leave for 30 minutes.

4. Thread the meat onto soaked wooden skewers in waves so the slices don't overlap.

5. Grill on a hot grill, griddle pan or under the oven grill for 3-4 minutes per side until slightly charred at the edges.

6. Sprinkle with the remaining yaji and serve with thinly sliced onion and tomato slices.

Tip: Suya is the evening grill of the Hausa street vendors of northern Nigeria and is now sold all over West Africa. The secret of yaji is freshly ground toasted peanuts; you can make a bigger batch, it keeps for weeks in an airtight jar. Slice the meat very thinly so it cooks quickly and stays tender.