Cook the rice according to the instructions. Chop the onion and sauté it in a little oil until soft.
In a bowl, mix the minced meat, cooked rice, egg, and sautéed onion. Season with salt and pepper and mix thoroughly. Shape the mixture into small balls.
In a pot, bring the broth to a boil. Add the meatballs and simmer over low heat for about 15-20 minutes until cooked through.
In a separate small pot, melt the butter, add the flour, and fry briefly to create a light roux. Slowly pour in the broth from the meatballs while stirring constantly to prevent lumps.
Add the cream and chopped dill to the sauce. Season with salt, pepper, and optionally, a little lemon juice for freshness. Briefly heat through, but do not boil.