01 - Combine mashed ube, granulated sugar, coconut milk, ube extract, and salt in a saucepan. Stir constantly over medium heat until smooth and slightly thickened, about 5 minutes. Allow the mixture to cool to room temperature.
02 - Blend shelled pistachios, whole milk, heavy cream, honey or sugar, vanilla extract, and salt until fully smooth. Transfer the mixture to a saucepan and gently heat over medium-low, stirring often for 5 minutes without boiling. Remove from heat and let cool.
03 - Pour the cooled ube mixture evenly into ice cream bar molds, filling each mold halfway. Freeze for 1 hour until set. Pour the pistachio mixture over the ube layer to fill to the top, and insert sticks. Freeze for at least 5 hours, until completely solid.
04 - Release bars from molds. For an optional garnish, drizzle with sweetened condensed milk and sprinkle with chopped pistachios before serving.