Yes, these are legitimate fruits, not undeveloped mangoes. I had thought these were known to Batanguenos alone but these are familiar in many regions. But I am told of a gentleman farmer in Tarlac who, upon seeing the paho fruits, thought that he had a diseased mango tree and promptly cut it down.
The paho has a bearable sourness that lingers in the tastebuds long after the meal. In Batangas, paho is eaten raw. Mixed with chopped tomatoes and onions flavored with soy sauce, it is the perfect accompaniment to fish, be it tawilis, tulingan or maliputo. I associate paho with an aunt who had the knack of mixing paho, tomato, and soy sauce into just the right blend that I always asked for a spoonful of the concoction deftly mixed with rice and fish. In some households, paho is pickled brine. But doiong so takes away the pungency that makes the fruit so special.