Lemon Meringue Cake

I made this for the first time for an Alpha group. Great stuff!

1 package lemon or yellow cake mix
3 eggs
1 cup water
1/3 cup vegetable oil

Filling:
1 cup sugar
3 Tbsp cornstarch
1/4 tsp salt
1/2 cup water
1/4 cup lemon juice
4 egg yolks, beaten
4 tsp butter
1 tsp grated lemon peel

Meringue:
4 egg whites
1/4 tsp cream of tartar
3/4 cup sugar

In a mixing bowl, combine cake mix, eggs, water and oil. Beat on low until moistened. Beat on high for 2 minutes or until blended. Pour into 2 greased and floured 9-inch rounds. Bake at 350 for 25-30 minutes or until toothpick comes out clean. Cool 10 minutes. Remove from pans to wire racks. For filling, combine sugar, cornstarch & salt in aucepan. Stir in water and juice until smooth. Bring to boil over medium heat; Cook and str 1-2 minutes until thickened. Remove from heat. Stir a small amount of hot filling into egg yolks; Return all to pan, stirring constantly. Bring to a gentle boil. Cook and stir for 2 minutes. Remove from heat. Stir in butter and lemon peel. Cool completely. For meringue, in a mixing bowl, beat egg whites and cream of tartar until foamy. Gradually beat in sugar on high until stiff peaks form. To assemble, split each layer into two layers. Place botom layer on an ovenproof serving plate. Spread with a third of the filling. Repeat layers twice. Top with fourth cake layer. Spread meringue over top and sides. Bake at 350 for 10-15 minutes or until meringue is lightly browned. Serve or refrigerate.