Tumbo is part of the passion fruit family. In English it's called banana passionfruit because its size and shape resembles a small thick banana. The orange, passionfruit-like cluster of black seeds and pulp is enclosed by a firm yellow skin.
Normally tumbos are quiet acidic and tart, therefore seldom eaten raw. You can best enjoy the flavor of Tumbo when processed to refreshing juices, jams and ice cream.