Named after postal worker Rudolph Hass, who purchased the seedling in 1926 from a California farmer, the distinctive purplish-black fruit has a thicker skin and smaller body than other varieties.

NPR: What's in a Name? The Avocado Story

Some farmers are successfully growing black pepper, pineapples and passion fruit.

ECONOMIST: A crop that refuses to die

Recent crowd pleasers include korokke (Japanese-style sweet potato cakes), casado (a Costa Rican meal of steak, rice, black beans, plantains and salad) and chicama cerviche de mero (grouper cerviche with passion fruit, japanese cucumber, red pepper, guava, red onion and tiger milk).

BBC: Innovative cuisine pops up in Buenos Aires