Melt 1 tablespoon butter in a large soup pot or Dutch/French oven. Saute celery, carrot, onion, bell pepper, and jalapeno until soft, about 10 minutes.
1 celery rib, 1 carrot, 1 small onion, 1 red bell pepper, 1 large jalapeno
Add garlic and saute for 30 seconds. Stir in dry mustard, thyme and Worcestershire.
Add half of the beer and bring to a simmer until volume of beer is reduced by half, about 5 minutes.
Add the chicken broth and bring back to a simmer. If you prefer a smooth soup, use an immersion blender to puree at this step. If not, proceed with next step.
2¼ cups low sodium chicken broth
In a separate small skillet, melt the remaining 4 tablespoons butter. Add the flour and cook for 2 minutes. Whisk this roux mixture into the soup and bring it to a simmer. Cook until the soup is thickened, approximately 8 minutes.
¼ cup flour
Remove the pot from heat. Slowly add the heavy cream and cheeses and the rest of the beer. You can add the cheese in several additions. Make sure the soup is not too hot when the cheese goes in.
1 cup heavy cream, 8 ounces sharp cheddar, 4 ounces smoked cheddar
Cook for an additional 5 minutes, stirring occasionally. Season with salt and pepper, if necessary. Add a bit more broth if the soup is too thick for your preference.
Serve with optional toppings of shredded cheese and sliced green onions.
Notes
For gluten free, use a measure for measure gluten free flour in place of all purpose.For low carb, substitute ½ teaspoon xanthan gum in place of flour when making roux. Add ¼ teaspoon, whisk well, then add the other ¼ teaspoon, whisk and cook briefly before whisking mixture into soup. The butter mixture will still resemble melted butter, but when added to the soup, the soup will thicken quickly.Source: Adapted from Food & WineYou're Gonna Bake It After Allbakeitafterall.com