Bake a prepackaged pie crust in oven. Zest two lemons. Squeeze the lemons to get a 1/2 cup of lemon juice (use a strainer to remove seeds). Set aside. Combine 1 cup of Sugar, 3 Tbs of corn starch, 2 Tbs of all purpose flour, pinch of salt, and 1 1/3 cups of water. Begin heating on medium high. Add lemon juice and lemon zest. Add 2 Tbs butter. Stir constantly. Separate 4 eggs and put egg white aside. Take 1/2 cup of mixture and slowly begin to add egg yolks, stir well. Add back into filling mixture. Add a few drops of lemon extract. Pour filling into baked shell and place in refrigerator for 10-15 minutes to cool merinque. Beat the 3 egg whites until they are very foamy. Slowly add in 1/3 cup of sugar mix on high until it peaks. Spoon on top of pie filling. Bake in oven a few minutes until merinque is brown.