In a large pot over medium-high heat, add the Italian sausage and cook for about 5-7 minutes, breaking it into small pieces until browned and no longer pink. Transfer to a plate lined with paper towels, leaving about 1 tablespoon of the grease in the pot.

In the same pot, melt 1 tablespoon of unsalted butter over medium heat. Add the mirepoix, stirring frequently, and sauté for 5-7 minutes until soft. Stir in the minced garlic for about 30 seconds.

Add the chopped baby gold potatoes along with the dried parsley, basil, salt, and pepper. Pour in the chicken stock and bring to a boil. Once boiling, reduce heat to medium-low, cover, and simmer for 15-20 minutes until fork-tender.

In a separate medium pot, melt the remaining 4 tablespoons of butter over medium heat. Whisk in the flour and cook for 1 minute. Gradually whisk in the milk until smooth and thickened, then stir in the heavy cream.

Once potatoes are tender, stir the creamy mixture into the pot. Add shredded Cheddar cheese in batches, allowing it to melt before each addition. Mix in the reserved sausage, adjusting seasoning with more salt and pepper.

Ladle the soup into bowls and serve with hearty buttered bread for dipping.