Heat the oil: Begin by heating vegetable oil in a large pot over medium heat. Allow the oil to shimmer slightly before adding the sausage.

Sauté the sausage: Add sliced andouille sausage to the pot and cook for about 3–4 minutes until browned. Remove and set aside.

Cook the vegetables: Combine diced onion, celery, and red bell pepper in the same pot and sauté for 5–8 minutes. Stir in minced garlic during the last minute.

Add the seasonings and broth: Stir in Cajun seasoning and other spices, then pour in chicken broth and add cubed potatoes. Mix well.

Simmer for tenderness: Reduce heat to low, cover, and simmer for 20–25 minutes until potatoes are fork-tender, stirring occasionally.

Incorporate cream and sausage: Return the cooked sausage to the pot and stir in heavy whipping cream. Heat through for about 5 minutes.

Garnish and serve: Ladle soup into bowls and garnish with parsley and cheddar cheese if desired. Serve warm.