Step 1

Heat milk in a saucepan over medium heat without boiling until steaming, about 4 minutes. Beat egg yolks and sugar in a large bowl. Slowly whisk hot milk into yolk mixture until well mixed; return mixture to saucepan and continue to cook on medium heat.

Step 2

Gradually stir peanut butter and vanilla extract into milk mixture until thoroughly combined, about 5 minutes. Pour peanut mixture into large bowl and cool for 15 minutes.

Step 3

Stir heavy cream and peanut butter cups into milk mixture, pour into an ice cream maker, and freeze according to the manufacturer's instructions.