Little Lime Tarts

Directions

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   1. Preheat oven to 325 degrees (F). Spray 24 mini-muffin cups with baking spray; set aside.
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   2. For tart shell dough: Cream butter and sugar together in a large bowl with an electric mixer, until fluffy.
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   3. Mix egg white into the creamed mixture until blended.
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   4. Add flour and a pinch of salt, mixing until well incorporated.
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   5. Use a small cookie scoop to scoop dough into the prepared mini-muffin cups.
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   6. Dip a few fingers into some flour, and press the dough into the cups (across the bottom and up the sides a little) to form a shell for the filling. Repeat with remaining dough. Dust fingers with more flour as needed to keep dough from sticking.
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   7. Once all of the dough has been shaped into shells, set them aside.
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   8. For the custard filling: Whisk eggs in a small bowl, until fluffy.
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   9. Pour sugar, and the melted/cooled butter into the beaten eggs; whisk until well incorporated.
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    10. Add the lime zest and juice, then whisk until just combined.
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    11. Pour filling into the tart dough shells, filling them 3/4 of the way full.
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    12. Bake for 20 minutes, or until the edges of the shells are very lightly browned, and filling is set.
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    13. Remove from oven, and cool in the pan on a wire rack for 5 minutes.
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    14. Gently run a paring knife along the edges of the tarts to remove them from the pan.
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    15. Cool completely on the wire rack.
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    16. To serve, dust with powdered sugar, or a dab of whipped cream or cream cheese frosting, and a sprinkle of citrus zest.
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    17. Store leftover tarts in an air-tight container in the refrigerator.