For the sauce: Mix the cherries, prune juice, apricots, tomato paste, tamarind concentrate, lemon juice, onion, garlic, cumin, allspice, cinnamon, 1 of cup water and salt to taste in a large saucepan and place over medium-high heat. Simmer the sauce until slightly thickened, about 30 minutes.
For the meatballs: Mix 1 pound of the ground beef with the ground rice in a large bowl. In a small bowl, mix the remaining 1/2 pound ground beef with the celery leaves, allspice and salt. Shape the beef-rice mixture into balls about 1 inch in diameter. Using your thumb, make an indentation in the center of a ball, shaping it into an oblong hollow. Stuff with 1 tablespoon of the beef-celery mixture, gently tamping it down with your finger to almost fill the hole. Pinch the rim to seal, making a small point on the end. Stuff the remaining balls the same way.
Add the meatballs to the sauce and simmer until the meatballs are cooked through, about 30 minutes. Serve over the rice.
A viewer or guest of the show, who may not be a professional cook, provided this recipe. It has not been tested for home use.