Make this delicious dip when avocados are plentiful and cheap. Don't be tempted to buy them if they're really soft because when avocados are over-ripe they develop an unpleasant turpentine-like flavor. Serve as a snack with store-bought or homemade tortilla chips or raw vegetable crudités.
Place the avocado flesh in a medium bowl and mash with a fork until semi-smooth. Add all other ingredients (reserving a little of the green part of the green onion, a little cilantro and a little of the chili for garnish) and stir to combine. Adjust seasonings to taste.
Transfer to a serving bowl and garnish with the onion, chiles and cilantro. Serve immediately with store-bought or Homemade Tortilla Chips or fresh vegetable crudités. Use within 3 to 4 hours of making.