1. In a large soup pot or Dutch oven, heat 1 tablespoon of vegetable oil over medium-high heat.
2. Add the sliced kielbasa and sauté until they turn brown and crispy, about 5-7 minutes. Remove them from the pot and set them aside.
3. In the same pot, melt 3 tablespoons of unsalted butter.
4. Add the chopped onion and diced carrots to the pot. Sauté for about 5 minutes, or until the vegetables begin to soften.
5. Stir in 2 teaspoons of minced garlic, salt and pepper. Cook for another 1-2 minutes until fragrant.
6. Sprinkle ¼ cup of all-purpose flour over the vegetables and stir well for 1 minute.
7. Pour in chicken broth, milk, and Worcestershire sauce while stirring continuously to prevent lumps from forming. Bring everything to simmer.
8. Return the sautéed kielbasa to the pot. Gently fold in the rinsed and drained Great Northern white beans.
9. On medium low simmer heat, allow the soup to simmer for about 15-20 minutes, or until the vegetables are tender and the flavors meld together.
10. Taste the soup and adjust the seasoning with salt and pepper if needed.
Serve hot, garnished with fresh parsley.
