In a heavy pan mix the egg yolks and sugar together. After mixing the egg yolks and sugar together, add the lemon juice and mix together. Heat over medium heat until mixture thickens to where it coats the back of the spoon. Do not let the mixture boil or really even almost boil or you will have curdling problems too.
Once the mixture thickens, remove from the heat. Add the butter and stir until melted. If curdling occurred (i.e. there are little bits of scrambled egg in your curd) strain through a fine mesh strainer.
After the curd has been strained, stir in lemon juice and vanilla extract. Place a piece of plastic wrap directly on the lemon curd (to keep it from getting a skin) for at least 1 hour or overnight.
For the Meringue
If using a stand mixer, fit with whisk attachment. Beat egg whites and cream of tarter with whisk attachment until foamy.
Add the sugar, 1 tablespoon at a time, beating until all incorporated.
Beat until stiff peaks form. Add vanilla and beat until incorporated.
For the Sugar Cookie Crust
In the bowl of your food processor add in sugar and flour. Take it for a spin to blend together.
With the blade still running, add in butter 1-2 tablespoons at a time until all incorporated.
Add in milk 1 tablespoon at a time until a smooth dough forms.
Chill for 1 hour or overnight.
Turn dough out onto floured surface and roll out to fit 9 inch tart pan. If your dough tears, simply patch it. Chill dough in pan for 1 hour or overnight.
Pre-heat oven to 350 degrees. Dock crust with fork. Bake at 350 degrees for 20 minutes or until crust is golden brown. Allow to cool completely.
To Assemble the Pie
Pour lemon curd into cooled pie crust. Spread evenly.
Spread or pipe meringue onto the lemon curd.
Use the kitchen torch to brown the meringue as desiered. If you don't have a kitchen torch, place pie under the broiler for only a minute or two to brown the meringue.
Enjoy!
Notes
*Makes 1-9 inch tart**Makes about 2 cups of lemon curd***Lemon curd recipe adapted from Martha Stewart Cupcakes