Fresh chillies are rated for their fieriness on the Scoville heat scale. It’s still debatable what the hottest chilli in the world is, but the Carolina reaper is said to be right near the top with a rating of 1.5 million Scoville units. It’s vital to use the right type and size of chilli or it can destroy your cooking efforts. Most of my recipes use thumb-sized red chillies and those are usually Fresno or serenade chillies. The green are either serenade or jalapeño with the latter being darker and rounder. Both have a heat of about 2500 to 8000 on the scale, so are perfect for cooking. Thai bird’s eye chillies (aka ‘scuds’) are very powerful with a rating of 100 000 to 225 000 on the scale, but can be used in small amounts as they are authentic to Thai cooking. If you scrape out the seeds and membranes, it removes the majority of heat, but if you’re using a scorcher like a Scotch bonnet or habanero, it’s still going to blow everyone’s head off.