Heat whole milk in a saucepan until it’s steaming but not boiling. In a separate bowl, whisk together egg yolks, granulated sugar, and cornstarch until smooth. Gradually combine hot milk with the egg mixture while whisking, then return to heat and stir until thickened.

Remove the custard from heat. Stir in butter and vanilla extract until melted and combined. Cool slightly before refrigerating until set, about 1-2 hours.

Take each sweet Hawaiian roll and cut a small hole in the top. Hollow out a bit of the insides to create space for filling.

Transfer the custard into a piping bag. Pipe chilled custard into each roll, being careful not to overfill.

In a saucepan, heat the heavy cream until steaming. Pour over chocolate chips and stir until smooth. Optional: add corn syrup for shine.

Dip or drizzle the filled rolls with the chocolate glaze. Let them sit for about 10 minutes to set.

Optionally dust with powdered sugar, top with whipped cream, or add fresh berries before serving.