I started by melting the butter in a large pot over medium heat. Then I tossed in the carrots, celery, onion, bell pepper, and mushrooms. Cooking them slowly lets the flavors deepen and makes the soup taste like it simmered for hours.
While the veggies softened, I boiled the diced potatoes in chicken broth in a separate saucepan. Doing this makes the potatoes absorb flavor right away, and they turn wonderfully tender. Once ready, I set them aside for the next step.
I added the cooked potatoes into the veggie pot and sprinkled in the flour. Stirring it in evenly prevents clumps, and once I poured in the half and half cream, the soup started turning creamy and thick. It was already smelling amazing by this point!
Next, I stirred in the bacon, dry mustard, hot sauce, and garlic salt. Finally, I added the shredded cheddar in small handfuls, stirring until smooth and gooey. The key here is not to boil once the cheese goes in—this keeps it creamy instead of grainy.
I ladled the soup into bowls and topped it with extra bacon bits, fresh green onions, and a sprinkle of cheddar. A side of crusty bread or garlic toast made it the perfect meal.