01 - Combine heavy cream and milk in a medium saucepan. Heat over medium until steaming but not boiling.
02 - In a bowl, whisk sugar and egg yolks until pale and slightly thickened.
03 - Gradually add about 1 cup of the hot cream mixture to the yolks, whisking constantly to temper the eggs.
04 - Return yolk mixture to the saucepan with remaining cream. Cook over low heat, stirring constantly, until mixture thickens enough to coat the back of a spoon (about 170°F). Avoid boiling.
05 - Remove from heat and stir in peppermint and vanilla extracts, plus optional green food coloring.
06 - Pour custard through a fine-mesh sieve into a clean bowl. Cool to room temperature, then cover and refrigerate at least 3 hours until thoroughly chilled.
07 - Churn chilled custard in an ice cream maker following manufacturer’s instructions.
08 - When ice cream is nearly finished churning, add mini chocolate chips and mix until evenly distributed.
09 - Transfer to a lidded container and freeze for at least 2 to 3 hours before serving.