Croissant Chicken Caesar Salad Sandwich

Name: Croissant Chicken Caesar Salad Sandwich
Ingredients: 2 cups all-purpose flour; 1 tablespoon garlic salt; 1 tablespoon smoked paprika; 1/2 tablespoon cayenne pepper; Salt (to taste); Black pepper (to taste); 3 large eggs; 1 cup buttermilk; 2 tablespoons hot sauce; 2 chicken thighs (boneless); 2 croissants; 1/2 teaspoon Dijon mustard; 2 tablespoons olive oil; 1 clove garlic (minced); 1 tablespoon capers (crushed); 3 anchovy fillets (crushed); 1 tablespoon lemon juice; 1/2 teaspoon red wine vinegar; Worcestershire sauce (dash); Tabasco sauce (dash); 3 tablespoons Parmesan cheese (freshly grated); 2 cups iceberg lettuce (chopped); 1 tablespoon butter (melted)