Heat oven to 350°. Spray rack of shallow roasting pan with nonstick cooking spray.

Cut each hen in half along backbone and breastbone from tail to neck with kitchen scissors. Place skin sides down on rack in roasting pan. Sprinkle with salt and pepper. Mix remaining ingredients; brush over both sides of hens. Insert meat thermometer so tip is in thickest part of inside thigh muscle and does not touch bone.

Roast uncovered 1 hour to 1 hour 10 minutes, turning once, until thermometer reads 180° and juice of hens is no longer pink when center of thigh is cut.