Momordica cochinchinensis, Gac Fruit, from the Vietnamese, is a species of plant in the melon and cucumber family Cucurbitaceae native to countries throughout Southeast Asia and to Queensland, Australia. It is notable for its vivid orange-reddish color resulting from a mix of beta-carotene and lycopene. The fruit are ovoid to broadly ellipsoid, about 6 in long by 4 in diameter, and are covered with numerous small spines on the skin.  They are initially green but turn a deep orange/red at maturity, and they contain numerous irregularly-shaped brown or grey seeds, which are enclosed in a bright red aril. Momordica cochinchinensis is one of these so called wonder fruits from Southeast Asian that has been traditionally used as both food and medicine in the regions in which it grows. It is a relative of the bitter gourd but Gac has been shown to be especially high in lycopene content. Relative to mass, it contains up to 70 times the amount of lycopene found in tomatoes. It has also been found to contain up to 10 times the amount of beta-carotene of carrots or sweet potatoes. You will need both male and female vines to cross pollinate for fruit which may prove a bit of a challenge in the UK even under glass.