In a bowl, whisk the egg yolks, granulated sugar, and salt until smooth. Stir in the whole milk and heavy cream until fully combined.

Transfer the mixture to a saucepan and heat over medium-low, stirring until it simmers and thickens slightly (about 2 minutes). Keep the heat low and whisk constantly to prevent curdling or chunks.

Remove the saucepan from heat. Stir in the vanilla extract. Pour the hot custard over the semisweet chocolate chips in a heatproof bowl and let sit for 1 minute. Whisk until the chocolate is fully melted and blended into the custard.

Pour the custard into individual serving cups or a large bowl. Cover the surface with plastic wrap, ensuring it touches the custard to prevent a skin from forming, and refrigerate for at least 4 hours, or until set. Garnish with fresh fruit, if desired.