Cook the sausage in 1 Tbsp olive oil and 1 Tbsp butter until browned and crumbled.
Add the onion, celery, carrots, and potatoes and sauté for 5-7 minutes.
Add the garlic and cook for 1 minute.
Melt the ¼ cup butter in the pot and whisk in the flour. Cook for 2 minutes.
Slowly whisk in the chicken broth and bring to a boil. Reduce heat and simmer for 10-15 minutes until thickened.
Stir in the half n half, salt, pepper, basil, oregano, Worcestershire sauce, and red pepper flakes.
Simmer for 5-10 more minutes until heated through.
