In a large bowl, combine the Suya spice mix, ground peanuts (if using), ground ginger, ground cumin, paprika, cayenne pepper, garlic powder, onion powder, and salt.
Add the groundnut oil to the spice mixture and mix well to form a paste.
Add the beef strips to the paste and coat them thoroughly. Cover the bowl and marinate in the refrigerator for at least 2 hours, or overnight for best results.
If using wooden skewers, soak them in water for about 30 minutes to prevent burning.
Thread the marinated beef strips onto the skewers, leaving a small gap between each piece to ensure even cooking.
Preheat your grill or barbecue to medium-high heat. If using a stovetop grill pan, heat it over medium-high heat.
Place the skewers on the grill and cook for about 3-4 minutes on each side, or until the beef is cooked through and slightly charred on the outside.
Enjoy your meal!