Graham Cracker Crust
3/4 cup sugar
3 tablespoons cornstarch
1/8 teaspoon salt
2 1/4 cups whole milk
4 large eggs yolks
2 teaspoons vanilla extract
1/2 cup semisweet chocolate chips
2 tablespoons butter, cut into 1/2-inch pieces
1/2 cup peanut butter chips
Prepare crust and allow to cool completely.
Combine sugar, cornstarch, and salt in medium saucepan. Whisk in milk and egg yolks. Place over medium heat; stir non-stop until mixture starts to thicken and boil. Keep on heat for 1 minute longer. Whisk in vanilla and remove from heat.
Immediately pour half of mixture into small bowl. Stir in chocolate chips and half of butter.
Using a clean whisk, stir the peanut butter chips and rest of butter into remaining custard. Whisk both mixtures (separately) until they are well-combined.