½cupfreshly squeezed lemon juice(about 2 or 3 lemons)
Preheat oven to 375°F.
Roll out the pie crust in a generous amount of rice flour, turning it often, adding flour as you do. There should be enough flour that there is still an excess remaining on the rolling surface after the dough has absorbed as much as possible. (The dough needs to be dryer than usual to withstand blind baking.)
Place the pie crust into the bottom and up the sides of a 9-inch pie plate so that it extends beyond the upper edges. Turn under the excess, pinching to hook it over the edge of the plate so that it hangs on rather than falling down during baking.
Prick the bottom and sides liberally with a fork.
Wet and crumple a sheet of parchment paper. Flatten it out again and gently place it over the bottom and sides of the pie crust. Line with pie weights to hold it in place.
Bake for 15 minutes. Allow to cool before removing the pie weights and parchment paper.
Preheat oven to 325°F.
Separate the three eggs putting the whites into a large mixing bowl, and the yolks into a medium one.
Whisk the cup of sugar and the flour together in a medium saucepan. Whisk in the water until smooth. Over medium heat, bring to a boil, stirring constantly. Boil for one minute.
Whisk egg yolks. Whisk half of the hot sugar-flour mixture into the yolks. Then whisk the yolk mixture back into the sugar-flour mixture on the stove. Cook for one more minute.
Remove from heat. Stir in butter and lemon juice.
Beat egg whites on high speed. As they begin to thicken and whiten, sprinkle in the tablespoon of sugar. Beat until soft peaks form. This is your meringue.
Pour the hot lemon filling into the baked pie crust. Smooth or pipe the meringue over the top.
Bake in 325F oven for 15 to 20 minutes, until the meringue is starting to brown up nicely.