1. Preheat oven to 350°. In a food processor, pulse together flour, sugar, cornstarch, orange zest, and salt. Add butter, then pulse until fine and crumbly. Remove bowl from food processor and stir in dried blueberries.
2. Measure 2 tbsp. mixture into each of 36 mini muffin cups*, pressing down firmly.
3. Bake until golden brown, about 15 minutes. Let cool at least a few minutes before serving.
*If you don't have mini muffin pans, press 1/4 cup mixture into each of 18 regular muffin cups and bake about 20 minutes.
Note: Nutritional analysis is per shortbread.