I have 12 ounces of 2-year-old trim. It’s pretty darn dry. I would like to use it to cook with but I’m worried about burning it during decarbing. Due to the volume and dryness, what would you suggest?
The process of decarbing is not likely to burn it, regardless of how dry it is.
That said, as old as your plant material is, it is likely already decarbed to a large degree. Age will also cause decarboxylation, not just heat. Hopefully, anything that has not decarbed due to age will decarb during the process of making your infusions such as marijuana butter or marijuana oil and in the process of cooking your recipes.
Likewise, if it were me in this instance I would probably cook with it as is without first decarbing.