Heat 1 oil in small skillet. Add onion. Sauté over medium heat allowing to lightly brown. Add a few grinds of fresh black pepper. Continue to sauté over low heat until tender and medium brown, about 5 minutes. Remove from heat and allow to cool.

Add the jalapeno, 1 teaspoon cilantro to the mojacete. Using the mortar, grind the ingredients down to form a bright green wet paste

Cut avocados in half, using a sharp knife to remove the seed by swiping down onto it, and turning to gently remove. Use a spoon to carve out the entire avocado halves

Place avocado in the mocajete & squeeze a half lime over. Using a gentle rocking motion, start to smash to form a chunky guacamole

Season with salt at this point, and taste. Adjust by adding more cilantro, or salt

Sprinkle tomatoes on top. Add additional sliced or minced fresh jalapeno on top for extra heat

Serve immediately. Any leftovers, seal immediately in a plastic bag, removing all the air, so that guacamole stays bright green