Bake your pie crust according to package/recipe directions and set aside.
Crack eggs in a small bowl, beat slightly with a fork and set aside.
In a large saucepan combine sugar and cornstarch. Whisk in milk and lemon juice until well combined.
Cook over medium high heat, stirring constantly, until mixture is thick and bubbling. Reduce heat to low and cook for two more minutes.
Whisk a small amount of hot mixture into your egg yolks. Pour egg mixture into pan, stirring constantly.
Bring mixture to a gentle boil and cook and stir for two minutes.
Stir in butter and lemon peel and remove from heat.
Once mixture has cooled stir in sour cream and add your filling to your crust.
Top with whipped cream and refrigerate until ready to serve.
