In a 2 qt saucepan:
1 1/4 c whole milk
2 egg YOLKS, beaten
1/4 c sugar
2 Tbsp cornstarch
Cook & stir over med heat until mixture boils & thickens.
Add:
1/2 tsp vanilla
1 Tbsp butter
Transfer custard to shallow dish.
Cover surface with plastic wrap.
Refrigerate 2 hours.
Meanwhile, in a 3 qt saucepan:
1 c blueberries
2/3 c sugar
3 Tbsp cornstarch
1 c water
On high, heat to boil.
Cook & stir for 2 min to thicken.
Stir in:
1 Tbsp lemon juice
1 Tbsp butter
Cool.
Stir in:
3 c blueberries
Spread custard in a baked pie shell.
Once blueberry mixture is cooled,
put on top of custard layer.
Refrigerate AT LEAST 3 hours to set.