Here are a couple of South Beach recipes for guacamole. Looks like a serving of Avocado is 1/3 whole while a serving of Guacamole is 1/2 cup. The important part is that you don't eat too much. These recipes came from
http://www.mizfrogspad.com/South_Bea.../Guacamole.htm
Perfect Guacamole (all phases)
1 clove of garlic, peeled
1/2 teaspoon salt
2 large ripe avocados
1 small ripe roma tomato
Juice from 1/2 fresh lime
With a fork, mash clove of garlic with the salt to make paste. Mash two ripe avocados until smooth. Add the garlic mixture. Grate one small ripe tomato into the avocado. Discard tomato skin. Add juice of 1/2 lime.
Fresh Guacamole (all phases)
2 ripe avocados (Hass)
1 tablespoon fresh lime juice
1 small sweet onion chopped
1/4 cup chopped parsley or cilantro
1 clove garlic, minced
Peel avocados and remove pits, reserving one pit. Mash avocado meat in bowl. Add lime juice and mix. Add remaining ingredients, mix well, add avocado pit then cover and refrigerate for 30 minutes before using. Adding the avocado pit helps to prevent the Guacamole from turning brown.