I am new here, and I read with a sense of malaise how many good people are searching for a good guacamole for their table and their guests; a quandary most recently complicated by the Kraft guacamole fiasco I read about here.
The perfect "guac" is simple but elusive. Elusive first:
1) Haas avocadocos. Period. Pear shaped, greenish-black, textured. Not shiny in original form. If they are shiny in your market, they have been waxed to keep them "fresh" longer, but it generally means they are rotting from within. Beware orangy-yellowish- brownish flesh. Avocados in the market ready to eat are called "para hoy" (for today), otherwise you have to nurture them at home until they are ready. Don't oversqueeze along the way.
2) Avocado, "aguacate" in spanish, is almost unique in an unfortunate respect in that it cannot be refrigerated (rots and loses all flavor within hours) and cannot be heated (rots and becomes chemically toxic in minutes). The myth about the seed..myth.
3) Have 50% more avocados than you think you need, because one third of the flesh will be unusable when you cut into them. No black, no brown, no yellow flesh, spoon it out or dump that whole fruit. The essence of good guacamole is good ripened fruit. That is 90% of your finished product. One yellowish or orange fruit will ruin an otherwise perfect batch. You will know when you have a good one; scoop out the marvelous deep green coating inside the rind for extra color and flavor.
4) Cut them, of course, to the pit around the oblate equator with a sharp paring knife into two hemispheres and pop out the seed, then scoop. Your hands remain clean.
5) Mash the pieces (or halves, if you are good with a spoon) with a fork on a plate and add fresh squozen lime juice, salt, and finely minced chilis or salsa picante to taste. Maybe a bit of cilantro. Don't overpower the avocado and lime flavors with the salsa. Salt should vary depending whether you are serving it with salted or unsalted tortilla chips, but it begs for salt. Serve immediately and at room temperature. All the recipes I saw with mayonnaise, mustard, extraneous spices, trash fillers and extenders, deviate from the genuine article. Sometimes I add a mashed roma tomato and reserve its juice to control the texture of the end product. It is a lucious, living, short-lived delicacy that should not be bought in a refrigerated container, if you have any respect for your guests or yourself. I welcome feedback from guac afficionados. For the many years that I lived in the Yucatan, guacamole and rock-and-roll-ee were my daily sustenance!