Cheers .Bung a load of Chillis in a kilner jar. Add 1 to 2 teaspoons of salt depending on size. Fill almost to the brim with water, with a small air gap. If you have another little pot of something to go in the top of the jar to weigh them down that's even better. Leave for as long as you can. Three weeks is enough though. Adding whole Cloves of peeled garlic optional.
Drain the Chillis and garlic, blend the shit out of it. Add the water you fermented it in to get it to your desired thickness.
If you are a bit of a wuss or have mentally hot Chillis, you could also ferment some peppers for the mix to tone it down a bit.
Got a massive Kilner full of chillies, garlic and a few diced peppers.