Taste Treasure of Niue in Alofi
No source under the exact name Taste Treasure of Niue was found in available research; the closest confirmed match is Savour Niue, the island's foodie festival typically held in March at Scenic Matavai Resort, featuring plantation tours, a cooking class, and wine matching.
Research into an event named specifically Taste Treasure of Niue did not turn up an independently confirmed match under that exact title.