How to Make It
Preheat oven to 325°F. Beat powdered sugar and 10 tablespoons of the butter in a large bowl of a stand mixer on medium speed until light and fluffy, about 3 minutes. Add 1 of the egg yolks, and beat just until combined. Stir together flour and 1/4 teaspoon of the salt; gradually add to butter mixture, beating on low speed just until flour mixture is incorporated. Transfer dough to a large sheet of plastic wrap; shape into an 8-inch disk, and wrap tightly. Chill 1 hour.
Divide dough into 6 equal pieces. Press each piece onto bottom and up sides of 6 lightly greased 4-inch tart pans with removable bottoms. Prick bottoms with a fork, and place on a rimmed baking sheet. Bake in preheated oven until golden brown, 18 to 20 minutes. Remove from oven, and cool completely, about 20 minutes.
Whisk together half-and-half, granulated sugar, brown sugar, cornstarch, and remaining 6 yolks and 1/4 teaspoon salt in a medium saucepan over medium. Cook, whisking constantly, until mixture just begins to thicken and bubble, about 10 minutes. Immediately remove from heat, and stir in remaining 1/4 cup butter until melted. Transfer mixture to a medium bowl, and let stand until cooled to room temperature, about 1 hour, stirring often. Stir in orange zest, orange juice, and lemon juice.
Spoon about 3/4 cup pudding into each cooled crust, and chill until set, at least 2 hours. Top evenly with orange segments and whipped cream just before serving.