Blueberry Lemon Crumb Bars

Bahan-bahan (24 porsi)

• 2 cups all purpose flour
• 2 tablespoons granulated white sugar
• 2 teaspoons grated lemon zest
• pinch of salt
• 1/2 cup (1 stick) chilled butter, (cut into pieces)
• 1 large egg
• 1 teaspoon vanilla extract
• 2 cups fresh blueberries
• 1/4 cup granulated white sugar
• 1/8 teaspoon ground nutmeg
• 5 tablespoons butter, (at room temperature)
• 1/2 cup packed brown sugar
• 3/4 cup all purpose flour
• 1/4 cup powdered sugar