A real guacamole is actually finely chopped fresh vegetables served raw. My friend, a chef, told me that authentic guacamole is actually more like a tartare than a purée. Never put your avocado in the blender; it ruins the integrity of the fruit. Not to mention it will turn an ugly grey color.
So first you remove the seed of your avocado, then you dice into small cubes.
Dice your onion into equally small cubes.
Dice or press garlic cloves into the mix, two or three depending on how hot you like it.
Squeeze the juice from one lemon over the whole bowl, toss gently, scoop with fresh corn tortillas.