Start by cooking diced bacon in a frying pan over medium heat. Stir occasionally until the pieces are golden and crispy. Transfer them to a paper towel-lined plate to drain excess grease. The crispy bacon will add plenty of flavor to the soup.
Using the leftover bacon fat in the pan, sauté your chopped onion, garlic, carrots, and celery. Cook for about five minutes, stirring occasionally, until the vegetables are softened and aromatic. This quick step adds depth and richness to your soup.
Transfer the sautéed veggies into your slow cooker. Add the soaked white beans, chicken broth, fresh rosemary sprig, a pinch of salt, and some cracked black pepper. Stir everything well to combine the ingredients evenly. Cover the slow cooker with the lid.
Set your slow cooker to low and allow the soup to simmer gently for 6–8 hours. This long, slow cooking process softens the beans and deepens the flavors, creating a deliciously creamy and hearty soup base.
About 30 minutes before serving, stir in the egg noodles and heavy cream. Cover again and cook on low until the noodles are tender. The cream will transform the soup into a silky, luscious masterpiece.
Once the noodles are cooked, stir in the crispy bacon. Remove the rosemary sprig and taste the soup, adjusting the seasoning if necessary. Ladle the soup into bowls, garnish with Parmesan cheese and parsley, and serve with a slice of crusty bread for dipping!