01 - Combine mashed ube, granulated sugar, full-fat coconut milk, ube extract, and salt in a saucepan. Stir constantly over medium heat until smooth and slightly thickened, about five minutes. Remove from heat and allow to cool to room temperature.
02 - Blend unsalted shelled pistachios, whole milk, heavy cream, honey or sugar, vanilla extract, and salt until fully smooth. Pour the mixture into a saucepan and gently heat on medium-low, stirring often, for five minutes without boiling. Remove from heat and cool.
03 - Pour the cooled ube mixture halfway into ice cream bar molds. Freeze for one hour until set. Layer the pistachio mixture over the ube, filling each mold to the top, and insert sticks. Freeze for at least five hours, until bars are firm.
04 - Remove frozen bars from molds. Drizzle with sweetened condensed milk and sprinkle with chopped pistachios to serve, if desired.