Pumpkin Tart with Pistachio Crust and Brittle

Name: Pumpkin Tart with Pistachio Crust and Brittle
Ingredients: ½ c. shelled unsalted pistachio nuts; ¼ c. confectioners' sugar; 1½ c. all-purpose flour; ¼ tsp. salt; ½ c. cold unsalted butter; 2 tbsp. cold unsalted butter; 1 large egg yolk; 2 tbsp. cold water; 1 can pumpkin purée; ¾ c. packed brown sugar; ¾ c. heavy cream; 3 large eggs; 2 tsp. pumpkin pie spice; 1 tsp. vanilla extract; ¼ tsp. almond extract; Pistachio brittle (recipe follows); Pistachio gelato; 1 c. sugar; ¼ c. water; .67 c. shelled unsalted pistachios