Willughbeia sarawacensis

About

Willughbeia sarawacensis, commonly known as tabo (Philippines) and kubal or kubal madu (Malaysia), is a large tropical vine-bearing plant with edible fruit native to Palawan and to the nearby island of Borneo. There are four related varieties known in Borneo: kubal asam or kubal taya, kubal tusu or kubal madu, kubal arang, and another much bigger cousin tabau.

Summary from Wikipedia