Ingredients

2 tablespoons unsalted butter 

3 tablespoons unbleached all-purpose flour 

2 teaspoons fresh thyme leaves 

2 teaspoons Dijon mustard 

1 bottle (12 ounces) lager beer 

4 ounces cream cheese, room temperature, cut into 6 to 8 pieces 

6 ounces extra-sharp cheddar, grated (about 1 1/2 cups) 

6 ounces Gruyere, grated (about 1 1/2 cups) 

2 teaspoons Worcestershire sauce 

Kosher salt and freshly ground pepper 

1/4 cup coarsely crushed pretzel rods, plus whole pretzel rods for serving 

Inner celery stalks, for serving 

Preparation

Melt butter in a medium saucepan over medium heat. Add flour; cook, whisking, about 2 minutes. Add thyme and mustard, then gradually add beer, whisking constantly until smooth. Bring to a boil and cook 1 minute more.

Reduce heat to medium. Add cream cheese, a piece at a time, whisking constantly until smooth. Whisk in cheddar and Gruyere, a handful at a time, until melted. Remove from heat. Add Worcestershire. Season with salt and pepper. Serve, sprinkled with pretzel crumbs, with pretzel rods and celery.