To cook the beef in a stockpot: Cut the beef into 1-inch cubes and brown in 1 TBSP butter, turmeric and black pepper for 10 minutes. Add the onion half and 3 cups of water and bring it to a boil then reduce the heat to medium low and cook until fork tender. This will take about 1 hour. Discard the onion half. If there is less than 2 cups broth by the time the meat is cooked, add more water.
Add the 4 whole limoo amani to a small bowl, add enough hot water just to cover it, and let it soak for 5-10 minutes.
In the large skillet saute the fried onions with the tomato paste for 2-3 minutes until aromatic. Add the cooked beef along with the broth, sauteed herbs, water, salt, pepper, crushed and whole limoo amani, and the cooked pinto beans to the skillet. Cover and simmer over medium low for 1 more hour, or until the meat and limoo amani are tender. If needed add more water.
If adding fresh tomatoes: Add the quartered tomatoes, cover and simmer over medium low for another 30 minutes until the sauce reduces.
Limoo amani (dried Persian lime) may be purchased from Middle Eastern markets.