Blueberry-Lavender Hand Pies

Prepare the Dough: Place flour, sugar, and salt in bowl of a food processor; pulse until combined, about 3 pulses. Scatter butter and shortening over top of flour mixture; pulse until mixture resembles coarse crumbs, 7 to 8 pulses. Add ice water; pulse until mixture starts to clump together, about 8 pulses. Scrape mixture out onto a lightly floured surface; knead just until it comes together, 2 or 3 times. Divide Dough in half; shape each half into a flat disk. Cover each disk in plastic wrap, and chill 4 hours.  

Prepare the Filling: Process lavender and 2 tablespoons of the sugar in a spice grinder or food processor until finely ground. Whisk together lavender mixture, cornstarch, salt, and remaining 2 tablespoons sugar in a small saucepan. Whisk in ¼ cup water, and bring to a boil over medium-high, whisking often. Cook, whisking constantly, until thickened, about 30 seconds. Remove from heat, and stir in blueberries and vanilla, lightly crushing half of the berries. Let stand until completely cool, about 30 minutes. 

Preheat oven to 400°F with oven rack in upper third of oven. Roll 1 chilled Dough disk to ⅛-inch thickness on a lightly floured surface; using a 5-inch round cutter, cut out 4 or 5 circles. Repeat procedure with remaining disk. Reroll scraps; cut out 2 or 3 more circles until you have 12 circles total. Spoon 1 tablespoon Filling in center of each circle. Moisten edges halfway around each circle with water. Fold circles in half over Filling; crimp edges with a fork to seal. Cut 2 to 3 (½-inch) slits on top of each pie. Place pies on a parchment paper-lined large rimmed baking sheet.

Bake in preheated oven until golden brown, 20 to 25 minutes. Transfer baking sheet to a wire rack, and cool 30 minutes. 

While pies cool, prepare the Glaze: Whisk together powdered sugar, milk, and vanilla until smooth. Drizzle Glaze over slightly warm pies. Serve warm, or let cool completely, about 30 minutes.