Cook Vegetables in a Pan: In a big pot, warm up the butter and olive oil on medium heat. Put the chopped onion, garlic, carrots, and celery. Cook the vegetables for 5-7 minutes, stirring from time to time, until they are soft and smell good.
Prepare roux: Put the flour on top of the vegetables and mix well for 1-2 minutes until the flour is cooked and a paste is formed. This makes the soup thicker.
Include broth and spices. Slowly pour the chicken broth while stirring to prevent clumps from forming. Include thyme, rosemary, salt, and pepper. Heat the mixture until it starts to bubble gently.
Make noodles and add chicken. Put the egg noodles in the pot and cook for 8-10 minutes until they are soft. Add the cooked chicken and mix it in.
Create a creamy texture: Lower the heat and pour in the milk or heavy cream. Mix the soup until it is smooth and hot, but be careful not to let it boil to avoid curdling.
Serve and decorate: Put the soup in bowls, add fresh parsley on top if you like, and serve while hot.
