Step 1

Place the onion, jalapeño, salt and half the coriander on a cutting board and use a fork to mash until juicy. OR do this in a mortar and pestle - grind into a paste.

Step 2

Scrape into a bowl, add avocado and remaining coriander, and mash to desired consistency.

Step 3

Do a taste test then adjust to your taste: salt, lime juice for sour, more chilli for spiciness.

Step 4

If using tomatoes, stir through.

Step 5

Serve with corn chips!