Easy Lemon Meringue Pie

1 graham cracker pie crust (I used a store bought one) 14 oz. can sweetened condensed milk 4 egg yolks (reserve the egg whites) 1/2 C. lemon juice In a bowl, combine the last 3 ingredients well. Pour into the pie crust and bake in a 350 degree oven for 15 minutes. For the Meringue: 4 egg whites 1/4 tsp. cream of tartar 1/4 C. sugar In a bowl, beat the egg whites until they begin to stiffen up, add in the cream of tartar and gradually add the sugar. Continue beating until stiff peaks form. Once the pie is baked, top the pie with the meringue and place back into the oven for 7 minutes or until the peaks are light brown. Allow the pie to completely cool before slicing. Store in the fridge.