Crush graham crackers with rolling pin or process for 30 sec. with knife blade in food processor. Combine cracker crumbs, butter, and 2 tbsp. of sugar. Stir until well moistened. Spread crumb mixture evenly into pie plate. Top with another pie plate and press down firmly. Refrigerate pie crust until ready to fill.
Beat egg yolks until they are thick. Add condensed milk and lime juice. Beat well. Pour thickened mixture into prepared graham cracker crust.
Combine egg whites and cream of tartar in a mixing bowl and beat until soft peaks form. Continue to beat, slowly adding ½ c. sugar. Continue beating until stiff peaks form. Spread meringue over pie filling. Bake in oven at 400° for 5 to 8 min. or until lightly browned. Refrigerate 2 to 3 hours or until ready to serve.
The pie filling will be yellow, not green. If a green color is desired, add 3 to 4 drops of green food coloring to pie filling while mixing.