Slowly whisk hot cream mixture into egg yolks while whisking constantly to prevent scrambling; this creates a silky, smooth custard rather than a grainy texture.

Pour the finished custard through a fine-mesh sieve to remove any cooked egg bits or undissolved chocolate, resulting in an impossibly smooth, restaurant-quality texture.

Use high-quality semisweet chocolate (60-70% cacao) rather than cheap chips for deeper flavor; finely chop it before adding so it melts evenly and completely into the custard.

Refrigerate the custard for at least 4 hours (preferably overnight) with plastic wrap pressed directly onto the surface to prevent a skin from forming and allow flavors to fully develop.

Reduce granulated sugar by 1-2 tablespoons if using premium chocolate, as quality chocolate adds its own natural sweetness and prevents an overly sugary dessert.