1. Combine coconut milk, garlic, curry powder, salt, pepper, and cayenne in a large bowl and stir until well mixed. Add chicken to the marinade and stir to coat well. Cover and refrigerate for at least six hours.
2. Preheat oven to 450 degrees Fahrenheit.
3. Thread chicken chunks onto skewers, leaving about half of each skewer empty for handling. Place them in a single layer on a large baking sheet. Cook for 10 minutes, then flip and cook for another five minutes or until cooked through. Alternatively, you can grill the chicken skewers.
4. Make the sauce: Whisk peanut butter, garlic, ginger, sesame oil, olive oil, soy sauce, and lime juice in a small saucepan and cook over low heat. Whisk until smooth.
5. Transfer chicken skewers onto a serving plate. Brush peanut sauce over the chicken. Top with sliced scallions.