Chocolate Pretzel Tart

Name: Chocolate Pretzel Tart
Ingredients: For the crust; 6 1/2 ounces pretzels; 7 tablespoons unsalted butter, room temperature; 1/4 cup powdered sugar; 1 egg; 1/4 teaspoon baking powder; 1/4 teaspoon salt; For the filling; 10 ounces excellent quality dark chocolate, divided; 1/4 to 1/2 cup roughly crushed pretzels; 4 tablespoons unsalted butter, cut into small pieces and softened; 1 1/4 cups heavy cream; For the caramel cream; 1/4 cup granulated sugar; 1 tablespoon water; 1 1/4 cup heavy cream, divided; Salt, to taste