I'm not sure that I have a scalable recipe as much as a simple list of ingredients and nebulous process (due to a lack of precision temperature control):
Take a couple of handfuls of raw pecan halves (enough to cover the bottom of whatever size (cast iron) pan you're using), throw them in, and put the heat on medium, and cover the pan with a lid.
At this point, I'm mainly trying to lightly roast the pecans (without burning them), and get their temperature somewhere close to the melting point of sugar.
Maybe check and move them around every minute or two, fiddling with the temperature (easy with a gas stove)? They seem to thrive on a little attention, and don't have very good thermal conductivity, so while one side is burnt, the other side is barely warmed..
Whenever I think they're (almost) roasted ( ~5 -10 minutes overall, a judgement call; the inevitable crumbs of broken pieces provide some information, if not definitive actionable knowledge), I then add 1 - 1 1/2 tablespoons of sugar (and a pinch or two of salt) into the pan.
Then, it's really fun to watch how the sugar starts to melt, monitoring the temp so that the sugar doesn't quickly caramelize or the pecans to burn. A great opportunity to throttle the amount of heat to the pan (and maybe wish for an IR thermometer, or a 160C - 180C temp controlled pan), and marvel at the temperature differences in different areas.
When "enough" of the sugar has melted, then I start to stir everything around to coat the pecans. You stir too soon, and you get a bunch of barely melted sugar stuck to the pecans. You stir too late, and the sugar caramelizes and turns brown or starts to smoke, and the pecans start to burn.
If it doesn't look like they're getting coated enough, sprinkle in more sugar, and try and get what's been added to melt, and not just glom onto what's already melted.
When you're happy with how everything is coated, then it's probably best to scrape them out of the pan onto a plate to cool. If you don't, then they'll solidify into a block that's stuck to the pan, and when you're scraping them out (or if you've let them cool as a lump in a bowl), they'll break into too many (tasty!) little crumbs and pieces, not the
I've also tried, once or twice, adding some red pepper flakes once the melting and stirring is underway, but gave it up after deciding that it didn't really add that much to the end result.
Pretty ad hoc, eh? Play with your food!