Fresh Blueberry Tarts

Heat oven to 400°F.

Combine flour, 2 tablespoons of the sugar, and the salt into processor, using several on/off motions. With motor running, quickly add butter, one piece at a time; process until mixture is crumbly. Do not over process. With motor running, add egg yolk; process just until dough begins to mass together. Remove dough from processor; gather into ball. Divide into 4 equal pieces. Flatten each piece with hand and press into bottoms and against sides of 4-1/2 inch tart pans with removable bottoms. Place in freezer.

Combine 2 cups of the blueberries, the remaining 4 tablespoons sugar, lemon juice (if using), the cinnamon, and nutmeg in medium bowl; toss to mix.

Remove tart shells from freezer. Spoon blueberry mixture into each tart shell, dividing evenly. Place tarts on baking sheet; bake until edges of crust are golden brown and blueberry mixture is bubbly, about 20 minutes. Remove tarts, in their pans, to wire rack to cool 10 minutes.

While tarts are still warm, loosen pastry from sides of pan with tip of knife. Carefully remove parts from pans; continue to cool on wire rack.

Spoon remaining 2 cups of blueberries on top of baked tarts. Sprinkle with confectioners sugar; top with julienne of lemon zest.