01 - In a saucepan, combine mashed ube, granulated sugar, coconut milk, ube extract, and salt. Cook over medium heat, stirring consistently, until smooth and lightly thickened, about 5 minutes. Remove from heat and allow to cool to room temperature.
02 - In a blender, combine pistachios, whole milk, heavy cream, honey or sugar, vanilla extract, and salt. Blend until the mixture is smooth. Transfer to a saucepan and gently heat over medium-low, stirring regularly, for 5 minutes without bringing to a boil. Remove from heat and let cool.
03 - Pour cooled ube mixture evenly into popsicle molds, filling halfway. Freeze for 1 hour, or until set enough for layering.
04 - Pour pistachio mixture over the set ube base, filling molds to the top. Insert sticks and freeze for at least 5 hours, until fully solidified.
05 - Remove ice cream bars from molds. Optionally, drizzle with sweetened condensed milk and sprinkle with chopped pistachios just before serving.