Preheat your oven to 350 degrees F. Allow your frozen mini pie crusts to thaw for about 15 minutes then place them on a baking pan.
Bake the mini pie crusts for 10-15 minutes and set aside to cool.
Using the double broiler method, on low heat (water of your double broiler must constantly be simmering), whisk 4 eggs, 4 egg yolks, ½ cup sugar, lemon juice and lemon zest for 6 to 8 minutes – or, until it is custard in consistency.
Remove the bowl of lemon mixture from the heat and allow to cool slightly. Cover with plastic wrap and refrigerate for an hour.
To make the meringue, start beating egg whites in an electric stand mixer. Start on slow and then slowly add the remaining sugar (1/2 cup).
Gradually increase the speed to high and beat for 10 to 12 minutes. The meringue is ready once it’s white and forms semi-stiff peaks.
If your mini pie crusts are in an aluminum tray, remove them from the tray.
Remove custard from the fridge and scoop the mixture into each one of your mini pie crusts. Top each lemon pie with meringue (I used a piping bag to add a dollop in the center of each one). Broil for 2 minutes or until top is browned just a bit.