Old Fashioned Caramel Pie

Directions

1. 1
   Leave oven on from baking pie shells. Whisk together the 1-2/3 cups sugar and cornstarch in a large (at least 2 qt.) microwaveable bowl until there are no more lumps from the cornstarch. Pour the milk into the sugar mixture and whisk together until smooth. Add the butter to the top of the mixture.
2. 2
   Microwave on high for 3 minutes. Whisk thoroughly. Microwave for 3 more minutes, whisk again. Have the egg yolks in a separate bowl. Beat them slightly. Add a tablespoon full of the hot mixture at a time to the egg yolks, stirring well after each addition. Do this until the yolk mixture is warm. (This will keep it from getting lumpy.) Then add the yolk mixture to the cooked mixture. Microwave in one minute increments, whisking each time, until the mixture is of pudding consistency. Whisk in the vanilla. Set aside.
3. 3
   Put the 2/3 cup sugar into a small iron skillet. Cook, stirring constantly, on high until brown and bubbling. It will look like it's going to boil over. Pour IMMEDIATELY into cooked filling and whisk thoroughly. Divide between the 2 pie shells.
4. 4
   Beat the egg whites and cream of tartar (if using) until foamy and slightly holding shape. Turn beaters on low speed. Add the 3/4 cup sugar. After sugar is mixed in, turn beaters on high again. Beat until meringue is hard to shake off a spoon (or it stays on beater when you turn off mixer and pull beaters out of bowl). Spread meringue onto filling all the way to the edges.
5. 5
   Bake about 10 minutes or until brown. Watch closely. Turn off oven, open oven door slightly, and let pies cool in oven for 1 hour. Let pies cool completely on counter. Spray plastic wrap with Pam, cover pies and refrigerate.