Mini Lobster Pot Pies

Name: Mini Lobster Pot Pies
Ingredients: 1 (5 ounce) lobster tail; 2 tablespoons butter, divided; 1 tablespoon sherry; 1 (8 ounce) bottle clam juice; 0.25 cup diced celery; 0.25 cup diced carrot; 0.25 teaspoon ground paprika; 1 teaspoon tomato paste; kosher salt and freshly ground black pepper to taste; 1 pinch ground cayenne pepper, or to taste; 1 tablespoon all-purpose flour; 0.333 cup cubed Yukon Gold potatoes; 1 sheet frozen puff pastry; 1 large egg, beaten; 1 teaspoon freshly squeezed lemon juice; 0.25 cup heavy cream; 1 tablespoon minced fresh tarragon