2 tablespoons unsalted butter
2 tablespoons all-purpose flour
2 cups milk
1/2 teaspoon kosher salt
3 cups (12 oz.) shredded Monterey Jack cheese
1 pound smoked pulled pork
1 cup bottled vinegar-based barbecue sauce
1 (15-oz.) can black beans, drained and rinsed
1 (12-oz.) package blue corn tortilla chips
3 plum tomatoes, seeded and diced
1/4 cup finely chopped fresh cilantro
1/2 cup sour cream
1/2 cup guacamole
1/4 cup pickled sliced jalapeño peppers