In a large pot, melt butter over medium-high heat. Add diced celery and onion, cooking until softened, about 5 minutes.
Sprinkle in the flour, stirring until the vegetables are coated and the flour is no longer visible, roughly 2 minutes.
Gradually pour in the half-and-half, followed by the chicken broth, stirring constantly to combine and prevent lumps.
Bring the mixture to a simmer, then add the shredded chicken, cheddar cheese, and hot sauce. Season with salt and pepper to your liking.
Reduce heat to medium-low and continue to simmer, stirring occasionally, until the cheese is fully melted and the soup is heated through, about 10 minutes.