Seafood Potpie

Ingredients

• Crust
• 1 cup (8 oz.) cold unsalted butter, cubed
• 2 cups (8 1/2 oz.) all-purpose flour, plus more for dusting
• 1 tablespoon granulated sugar
• 1/8 teaspoon cayenne pepper
• 1/2 teaspoon kosher salt
• 1/2 cup water
• Filling
• 1/2 fennel bulb, cut into 1/2-inch pieces (about 1 cup)
• 4 carrots, cut into 1/2-inch pieces (about 1 cup)
• 4 celery stalks, cut into 1/2-inch pieces (about 1 cup)
• 1/2 celery root, cut into 1/2-inch pieces (about 1 cup)
• 1/2 yellow onion, cut into 1/2-inch pieces (about 1 cup)
• 1 pound baby red potatoes, cut into 1/2-inch pieces (about 1 cup)
• 4 thyme sprigs
• 3 garlic cloves
• 1 tablespoon olive oil
• 2 1/2 teaspoons kosher salt, divided
• 3 tablespoons unsalted butter
• 3 tablespoons all-purpose flour
• 1/8 teaspoon ground mace
• 1/4 teaspoon onion powder
• 1/4 teaspoon garlic powder
• 1 bay leaf
• 3 cups whole milk
• 1 pound boneless, skinless grouper, swordfish, or mahimahi fillets, cut into 1 1/2-inch pieces
• 1 pound dry-packed sea scallops, halved
• 1 pound peeled and deveined medium-size raw shrimp
• 1 teaspoon smoked paprika
• 2 tablespoons sherry
• 1/4 cup finely chopped fresh flat-leaf parsley