Peel the onions, cut in half and then cut into large cubes. Rinse the tomatoes, hull, cut in half and dice. Rinse the peppers, trim, cut in half, remove the seeds and pith and cut into cubes. Peel the garlic and chop.
Rinse the meat, pat dry and season with salt and pepper. Heat the butter in a large saucepan and brown the meat on all sides. Add the onions, peppers and garlic and sauté briefly. Pour the broth into the pan and bring to a boil. Reduce the heat, cover and simmer for about 40 minutes over medium heat. Remove the lid and bring back to a boil. Cook until the liquid is reduced by 1/2. Add the tomatoes and bring back to a boil. Add the paprika and season with salt and pepper. Serve with potatoes, if desired.