Step 1.
Place the peanuts in a food processor and process until finely chopped.
Step 2.
Add the paprika, onion powder, ground ginger, ground scotch bonnet pepper, garlic powder and 1 tablespoon of vegetable oil and pulse until combined.
Step 3.
Separately blend the calabash nutmeg with a pinch of black pepper. Sift this into the peanut mixture.
Step 4.
Thinly slice the sirloin steak and place in a large bowl or shallow dish. Drizzle with vegetable oil, sprinkle with 2 tsp salt and toss to coat.
Step 5.
Add peanut mixture and toss again to coat. Refrigerate, covered, for 2 hours.
Step 6.
Drain the beef, discarding marinade, then thread it onto metal or soaked wooden skewers.
Step 7.
Dice the onion and tomato.
Step 8.
Grill the beef, covered and turning occasionally, over medium-high heat for 10-15 mins, or until it reaches your desired doneness. Serve with the diced onions and tomatoes.