Add the peppers, garlic cloves, salt, and water in a food processor. Process until you reach the texture of a chunky salsa.
Transfer to a clean glass container and cover with a cheesecloth. Leave on the counter at room temperature for 24-48 hours.
After 1-2 days, stir in the apple cider vinegar. Leave on the counter, covered with a cheesecloth for 5-7 days (if you have time, go the full week!).
After 1 week, transfer to a blender and purée until smooth. If it's very thick add more water (and/or vinegar to taste) to thin. Optional: strain the sauce through a mesh strainer or cheesecloth lined strainer. Squeeze out all the juice from the remaining pulp. Straining will make a thinner sauce, so wait to thin the sauce if you are straining it.
Transfer to a clean jar or hot sauce bottle and refrigerate. It will last for several months.
Separation is normal, shake before use.