I do a simple stove top method. Simmer hot peppers of choice with small amount of onion and garlic in a brine of apple cider vinegar, water and sugar to balance. I use habaneros and Thai chili peppers regularly. I strain and purée, adding back the brine to desired consistency. I put in mason jars and use it up quickly, but it lasts quite a while in the fridge. Super flavourful, spicy and balanced.
I made some fermented hot sauce last year and having made both fermented and non-fermented hot sauce there is no comparison. Fermented is much better flavor. Besides you get the benefits from probiotics as well with the fermented. I made it from a blend of Ghost Pepper and regular bell pepper to tone it down a tad. It was still brutal.
At the moment I'm the only one eating hot sauce, and I'm not eating a lot. We have also made lots of "pique" over the years. Super simple. Take fresh hot peppers -- a mix of your favourites -- and stuff them in a jar. Add some peeled garlic and cider vinegar that has a bit of added salt and sugar, and then just let it sit. Good on eggs, stirfries, etc.
Some people add more vinegar when they run low. When I make chilaquiles I pull a nice pickled jalapeno out of the jar and dice it up.
The key to fermenting is to have enough salt to prevent the bad bacteria to grow. Use non-iodized salt and make sure the water, if you use any, is not chlorinated. The good bacteria will generate lactic acid which will make it tart. The longer you ferment the tarter it will get. If it is not enough you can do like @Old Hippie suggested above and add some vinegar so your liking. I would just do that after fermentation so you can judge it better. there are plenty of instruction videos and such out on the tube regarding all this.
I fermented a batch of tabasco peppers last year. They came out really good. Had to thin it down quite a bit and it's still about double the heat of store-bought tabasco sauce but it has an excellent flavor.
I currently like Hell Fire sauce (Jamaican style). That one is fairly easy, Habanero or scotch bonnet peppers, a tablespoon or so of canning salt, between 5-10 garlic. Cover everything with white vinegar. Blender until it's chunky (not soup). And that's it. I keep it in the refrigerator in a mason jar. I usually finish my jar in a month and they are still ok because of the vinegar.
There are 3 types of sauces that you can make. Raw, cooked, or fermented (at least, that's the 3 ways that I know).
I prefer fermented. I normally put what I want and the peppers that I can find (in my garden or at the grocery). I usually use bird's eye chilis. I add things like garlic and onions. Sometimes fresh ginger, etc. I add distilled water and calculate 2% salt for the total of my volume (ferment + water). I need to make sure that everything is covered with water at all times (to avoid mold). I leave it in a dark, shady corner for 3 weeks and check it daily. If the water evaporates, I add more distilled water. I keep a bowl under the jar in case it overflows. After 3 weeks, blender (this time, like soup). I transfer everything in a cleaned bottle and that's it.
Two out of 16 plants survived last year's hurricane, but they are producing some good-looking Datil peppers. Datils are associated with St. Augustine Florida ... but they'll grow anywhere. https://en.wikipedia.org/wiki/Datil_pepper...
I just jarred these up about an hour ago. One will be a fermented hot sauce with garlic, ginger, Fresno peppers, & habanero peppers. The other is a chili honey with garlic, Fresno, habanero, and jalapeno peppers, with some saffron threads.
I love hot peppers in my saurkraut, but I haven't liked any of my three fermented pepper hot sauce attempts. I don't remember my recipes, but I do remember having to use more spicy peppers each time. A lot of the heat disappeared in the fermentation.
I like fresh or cooked habanero-based sauces a lot more than any fermented I've tried.