The Hass variety was actually discovered growing from a chance seedling in the 1920's. This variety is known for its fairly thick skin that turns near black when fully ripe. Besides, the flavor of its flesh reflects its texture - creamy and smooth with a nutty and sweet finish. Like all avocados, Hass avocados are high in healthy fats, vitamins C, E and B, potassium, and folic acid. As a matter of fact, avocados are high in antioxidants, including lutein and zeaxanthin, which are very important for eye health, not to mention that they lower your risk of macular degeneration and cataracts.