Put remaining 2 tablespoons of olive oil in a medium saucepan and put over medium heat. Add the tomatoes and onions and stir for 5 minutes. Add the marinated beef and cook for another 10 minutes, stirring consistently, to ensure even cooking. Once the liquid in the pan begins to boil continue cooking for another 5 minutes. Remove the pan from heat and stir in the jalapenos. Serve warm with desired bread as an optional side.