Add bacon to a large pot over medium-high heat. Cook, stirring often, until the bacon starts to brown, about 5 minutes.

Add the red onion, celery, and butter. Sauté until the onion softens, about 5 minutes.

Add the flour. Stir, and continue stirring for 4-5 minutes until the flour is cooked over medium heat.

Whisk in the chicken stock and bring to a boil. Boil for 1 minute then reduce heat to a simmer and cook for 15 minutes, stirring occasionally.

Add milk. Bring to a simmer and continue to simmer slowly for 15 minutes.

Remove pot from the heat and stir in cheese, hot sauce, Worcestershire sauce, and salt and pepper to taste until the cheese is melted.

Stir in warm beer.

Serve garnished with chopped green onions if desired.