Famously mashed to make guacamole, avocados are a unique fruit; they have a yellow-green, buttery, smooth, mild-tasting flesh surrounding a large stonelike pit. There are several varieties of avocado. The two most widely available are the Haas and the Fuerte. The Haas has a rough texture and a skin that ranges from dark green to purpley black. The Fuerte is larger with smooth emerald-green skin. Whichever kind you choose, be sure that it's ripe before eating it; the fruit is ripe when it's gives a little when pressed.
1 large avocado = about 1 1/4 cup diced
Avocados only ripen once picked. Some markets will offer avocados that are ripe and ready to eat as well as those that need more ripening, but more often than not, you will encounter rock-hard avocados that need a few days at room temperature to ripen. The biggest mistake people make when buying avocados is choosing ones that are too soft. To sort the ripe from the unripe at the store, cradle an avocado in your hand and press gently—don’t poke or you’ll bruise it. A perfectly ripe avocado should feel firm with a slight give, not soft.
Once the flesh of an avocado is exposed, it discolors quickly so it's best to use and serve them right away. The addition of lemon or lime juice will help slow down the discoloration, as will storing it, tightly wrapped, in the refrigerator.
To neatly remove the pit, slice the avocado in half lengthwise around the pit. Twist the two halves in opposing directions and pull them apart. Carefully but firmly chop the blade of a chef's knife into the pit and use the knife to twist pit out of the avocado. (To dislodge the pit from the knife, scrape it against the inside edge of the sink or grasp it with a kitchen towel to pull it off the knife.) To remove the flesh from its skin, hold the avocado in the palm of your hand and, using a large spoon, carefully scoop out the flesh in a single piece. When an avocado is soft and ripe, it's usually easier to slice or dice it before removing its skin. Once halved and pitted, use a paring knife to cut the avocado diagonally into 1/4-inch (or wider) slices, without piercing through the skin. If a dice is your goal, make a second set of diagonal slices perpendicular to the first. To remove the sliced or diced avocado from its skin, hold the avocado in the palm of your hand and, using a large spoon, carefully scoop out the slices.
Leave avocados out at room temperature to ripen if needed. (To speed ripening, put them in a bag with a banana.) Once the avocados are ripe, keep them refrigerated where they should last a few more days.