First, remove the stems from the hot peppers. Weigh the peppers and note down the weight.
Roughly chop the hot peppers and place in a mortar. Removing the seeds at this point creates a nice looking sauce, but it will be less spicy than if you leave the seeds.
Mix the salt (3% of the weight of the hot peppers you weighed in Step 1) into the peppers and mash.
Boil a jar to sterilize. Transfer the mixture to the jar and add the grain vinegar (50% of the weight of the hot peppers you weighed in Step 1) and combine. Let the sauce sit in the refrigerator for 2 weeks.