Melt butter in heavy skillet. When pan is quite hot, add meat and brown about 15 minutes, turning until good and brown. Then pour in 2 cups boiling water and stir. Add garlic, onion, salt, and pepper. Cover, turn heat to low and simmer for 1 hour. Then remove garlic, add carrots, and cook 45 minutes longer. Make a paste of flour and cold water and add to meat and stir. Simmer for 15 minutes longer. Serve on 6 portions of mashed potatoes.