Bring a pot of water to the boil and add the tomatillos, jalapeno, onion, garlic, and salt. Reduce the heat and simmer gently for 5 to 10 minutes until the tomatillos are soft but have not burst. Drain and reserve cooking liquid. Add the cooked vegetables to a blender with the coriander leaves and lime juice.
Pour in 60ml of the reserved cooking liquid and process to a coarse puree - be careful when you process the hot liquid as it will expand - so make sure you hold the lid down firmly. Taste and adjust seasoning with more coriander, lime juice, or salt according to taste.
Prepare corn crisps. Preheat oil to 190°C. Cut tortillas into large wedges and deep-fry in batches until golden and crispy, approximately one to two minutes. Season immediately with salt so it sticks to crisps and serve warm with tomatillo salsa.
* When blending hot liquids: Remove liquid from the heat and allow to cool for at least five minutes. Transfer liquid to a blender or food processor and fill it no more than halfway. If using a blender, release one corner of the lid. This prevents the vacuum effect that creates heat explosions. Place a towel over the top of the machine, pulse a few times then process on high speed until smooth.