In a small saucepan over medium heat, melt 4 tablespoons of butter with 1 cup of chocolate chips. Stir in 1 cup of granulated sugar and 1 cup of evaporated milk, simmer for 5 minutes, then add 1 teaspoon of vanilla extract and a pinch of salt. Cool completely.

Whisk together 4 egg yolks and 3/4 cup of granulated sugar until pale. Heat 2 cups of whole milk until 165°F, then slowly whisk into the egg mixture. Cook over low heat until thickened, about 5 minutes.

Strain the mixture through a fine-mesh sieve into a clean bowl and let it cool slightly.

Combine the strained mixture with 2 cups of heavy cream and 1 tablespoon of pure vanilla extract in a large bowl, whisking until smooth.

Cover and chill in the refrigerator for at least 4 hours.

Slice 1 cup of mini Reese’s peanut butter cups in half and set aside.

Pour the chilled mixture into an ice cream maker and churn according to the manufacturer’s instructions until thickened.

Layer the churned ice cream in a container with hot fudge sauce and peanut butter cups, repeating the process.

Freeze for at least 4 hours before serving.

Serve and enjoy, optionally garnished with additional hot fudge or peanut butter cups.