Remove fat from meat. Cut meat to fit into 3 1/2- or 4-quart slow cooker.
Cook meat in large skillet with oil over medium heat until brown on all sides.
Drain off fat and place meat in cooker, add water and sprinkle meat with 2 teaspoons fresh dill, salt and pepper.
Cover and cook on low-heat for 10 to 12 hours or on high-heat setting for 5 to 6 hours.
Transfer meat to serving platter, reserving cooking liquid. Cover meat with foil to keep warm.
Pour cooking liquid into a glass measuring cupamd skim off fat.
Measure 1 cup cooking liquid and set aside (discard any remaining liquid).
In a small saucepan combine the yogurt and flour. Stir in the reserved 1 cup liquid and remaining dill. Cook and stir over medium heat until thickened and bubbly. Cook and stir for 1 additional minute.
Pour some of the sauce over meat. Serve remaining sauce on the side.