Spray inside of 6-quart slow cooker with cooking spray. Combine sauce, onion and olives in slow cooker.
Spray large skillet with cooking spray; heat over medium-high heat. Sprinkle chicken with cumin, paprika and pepper. Cook chicken 3 to 5 minutes or until browned on each side, turning several times. Place chicken in slow cooker. Add water to skillet; stir to loosen brown bits from bottom of skillet. Transfer liquid to slow cooker.
Cover; cook on LOW 8 hours or HIGH 4 hours. Serve with cooked couscous. Sprinkle with almonds, if desired.