Pound the chicken breasts to an even 1/2-inch thickness between two pieces of wax or parchment paper. Cut the breasts into 1-1/2" pieces and set aside.

Make the marinade by combining the soy sauce, dark brown sugar, lime zest, vegetable oil, garlic, curry powder, ginger, cardamom and salt in a large bowl. Add the chicken pieces to the bowl and mix until chicken is evenly coated. Cover the bowl with plastic wrap and marinate in the refrigerator for at least 4 hours or overnight.

Make the sauce by whisking together the coconut milk, peanut butter, brown sugar, soy sauce and red curry paste in a medium saucepan. Bring to a simmer, then cook over medium heat, stirring occasionally, for about 3 minutes. Set aside.

Preheat the grill to high heat. Meanwhile, thread the chicken pieces onto skewers. Grease the grill. Place the skewers on the grill and cook for about 10 minutes, turning once, or until the chicken is cooked through. Serve the chicken skewers with the Coconut-Peanut Sauce