In the bowl of an electric mixer, beat the butter for about 1 minute. Add the powdered sugar and beat for another 2 minutes at medium speed.
Bake the pie crust for about 12 minutes, until the sides are golden.
Remove the pie crust from the oven once golden all over. Then make the filling.
Condensed Milk Lemon Pie Filling
Crust: You can make the crust ahead, roll it out, line the bottom of the tart pan, cover it with plastic wrap and keep it in the freezer for up to 3 weeks, or in the fridge for up to 2 days.