Shortbread Tarts with Lemon Filling

Shortbread Tarts with Lemon Filling
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Source: Appeal Magazine

Shortbread crust

1 cup butter softened
1/2 cup icing sugar
1 1/2 cups all-purpose flour
1 Tablespoon Cornstarch

Filling

1/2 cup fresh squeezed lemon juice
1 Tablespoon grated lemon zest
1 cup granulated sugar
3 eggs well beaten
1/2 cups butter at room temperature
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Preheat oven to 325°F. Combine shortbread ingredients in the bowl of an electric mixer. Mix to form dough. Divide dough into 24 pieces. Pat each portion of dough into a 1 1/2" (4 cm) tart tin, using your fingers to shape it into a shell. Prick the bottom of each tart with a fork. Bake 10 minutes and then prick bottoms again as the shells puff up. Bake an additional 10 minutes. Remove from oven and allow tarts to cool on a wire rack before filling.

To prepare lemon filling, combine juice and zest in a double boiler. Whisk in sugar, eggs and butter, blending well. Place over gently boiling water and whisk constantly until mixture thickens. Cool before using to fill tart shells. Lemon filling can be prepared ahead of time
and stored in the refrigerator.

(Note: I did not cook using a double boiler. I added the juice, zest, sugar and butter to the pot and brought to a boil. Then I beat the eggs and added some of the hot mixture to the eggs to temper before adding this egg mixture to the pan. I continued to stir over low heat until the mixture thickened.)