Make suya spice by mixing the peanut butter powder, paprika, ginger, garlic, onion, nutmeg and chilli powder in a bowl.
Cut the beef into thin slices.
Pour in a bowl and toss in three tablespoons of suya spice with some salt. Make sure all the meat pieces are covered.
Switch on the air-fryer and set to 160 °C.
Place the meat pieces on the tray in a single layer and close.
After 10 mins, the meat should be cooked and will be starting to dry out. Add a sprinkle of the suya spice over the beef pieces.
Leave for another 5 mins.
Remove from the air fryer.