Pumpkin Tart with Pistachio Crust and Brittle

Name: Pumpkin Tart with Pistachio Crust and Brittle
Ingredients: 1/2 c. shelled unsalted pistachio nuts; 1/4 c. confectioners' sugar; 1 1/2 c. all-purpose flour; 1/4 tsp. salt; 1/2 c. cold unsalted butter; 2 tbsp. cold unsalted butter; 1 large egg yolk; 2 tbsp. cold water; 1 can pumpkin purée; 3/4 c. packed brown sugar; 3/4 c. heavy cream; 3 large eggs; 2 tsp. pumpkin pie spice; 1 tsp. vanilla extract; 1/4 tsp. almond extract; Pistachio brittle (recipe follows); Pistachio gelato; 1 c. sugar; 1/4 c. water; c. shelled unsalted pistachios