To add flavor to bolognese, you may start by sautéing finely chopped onion, garlic, and celery in olive oil until they are soft. This will create a base that is rich and sweet. You may then add in minced meat, such as beef, pork, or a mixture of both, and cook it until it is browned. To enhance the aroma and taste of the bolognese sauce, you can add herbs and spices such as oregano, thyme, bay leaves, and black pepper. Wine and tomato paste can also be added to intensify the flavors. Finally, cooking the sauce slowly over low heat for an extended period can help to develop rich and complex flavor.