Melt the lard or heat oil in a large saucepan over medium high heat. Add the meat and brown well on all sides. Add the onions and sauté for 5 minutes, or until tender. Add the tinned tomatoes, jalapenos, fresh tomatoes, cumin, garlic, salt and pepper.
Reduce heat to low, cover and simmer for 30 minutes to 1 hour, or until meat is tender. If mixture is too thick, add water as needed. Or if mixture is too thin, cook uncovered to allow liquid to evaporate.