1 Cut avocados in half. Remove seed. Scoop out avacado from the peel, put in a mixing bowl. (See How to Cut and Peel an Avocado.)
2 Using a fork, mash the avocado. Add the chopped onion, cilantro, lime or lemon, salt and pepper and mash some more. Chili peppers vary individually in their hotness. So, start with a half of one chili pepper and add to the guacamole to your desired degree of hotness. Be careful handling the peppers; wash your hands thoroughly after handling and do not touch your eyes or the area near your eyes with your hands for several hours.
Keep the tomatoes separate until ready to serve.
Remember that much of this is done to taste because of the variability in the fresh ingredients. Start with this recipe and adjust to your taste.
3 Cover with plastic wrap directly on the surface of the guacamole to prevent oxidation from the air reaching it. Refrigerate until ready.
4 Just before serving, add the chopped tomato to the guacamole and mix.
For a very quick "guac" just take a 1/4 cup of salsa and mix it in with your mashed avocados.
You don't need to have tomatoes in your guacamole.
To extend a limited supply of avocados, add either sour cream or cottage cheese to your guacamole dip. Purists may be horrified, but so what? It tastes great. In fact, guac with some cottage cheese added to it is my favorite.