Preheat oven to 375 degrees.
Line a roasting pan with foil and then place a roasting rack inside of the pan and spray with oil. Both of these suggestions allow for easier pan and rack clean up.
Season all sides of hens with kosher salt and freshly ground pepper.
Place hens on the rack breast-side down. You’ll know you’ve done it correctly if the wings are facing up.
Transfer the pan to the middle rack in the oven and cook for 40 minutes undisturbed. The skin will be browned and crispy.
While the hens are cooking, make the sauce. Place the raspberry preserves, Dijon mustard, water, and rosemary or thyme in a bowl and mix until combined. Set aside.
Remove pan from the oven and brush on the first coating of the raspberry sauce all over the hens - sides, front and back. Place pan back in the oven. Repeat saucing after 5 mins. The sauce will be caramelized and baked-on. If this isn’t the case, heat the broiler and broil hens for one minute or less (keep a close eye of them to avoid burning!). Saucing time is 10 minutes, total cooking time is 50 minutes.
Remove pan from the oven and let rest for 10 minutes.
Transfer hens to individual plates or a platter. Serve with wild or black rice and garish with thyme or rosemary sprigs.