i have a 3.5 butt and a pork tenderloin in the freezer. is it ok to do together since times vary so much and how long to smoke?thanks
Yes, they can be done together. As you noted, the tenderloin will cook much, much faster than the butt.
Just put the one that will be finished (fully cooked) above the one that will stay in longer . What you want to avoid is uncooked meat drips on the cooked product.
If you want them done near the same time, another option would be to first cook the butt, put it into FTC, and while it is resting cook the tenderloin, which really doesn't need the FTC treatment.