Sour cream lemon pie

I had never tied a cooked cream pie prior to this and was so happy with how this turned out.  Yummy!  I will say it goes quickly on the stove so it's best to have everything measured out and ready to go...

1 c. sugar
1/2 c. flour
1/2 tsp salt
2 c. milk
1/2 c. sour cream
3 egg yolks
1/4 c. butter
1 1/2 tsp lemon zest or more to taste
1/4 c. lemon juice
1 baked pie crust (9 inch)

Combine sugar, flour, and salt.  Gradually add milk.  Cook and stir on medium heat until thickened and bubbly.  Reduce heat, cook and stir 2 more minutes.  Remove from heat.

Beat yolks slightly.  Gradually add 1 cup of mix into yolks.  Return yolk mixture to saucepan, and bring to boil.  Cook and stir 2 more minutes.  Remove from heat and stir in butter, peel and juice.  Fold in sour cream and pour into baked shell.  Cool.  Top with homemade whip cream.