I don't claim to be in the same league as a lot of the cooks here, but I have yet to produce a "bad" brisket on these cookers. (Don't ask about my stick burner days. I wasted a lot of good meat and precious time). Here is my basic cheat sheet. Others may agree or contradict. I'm fine either way...
- Get a decent brisket as budget allows. I find that separated flats are less predictable and actually more temperamental to cook. My sweet spot seems to be in the 14 to 18 pound range. I preferably aim for prime or better and always full packers.
- Trim to about 1/4 inch of fat everywhere as best you can. You can decide if you're going to separate the point and flat based upon how big the "fat ribbon" is between the two muscles. I rarely separate even when I get a little crazy cutting out the inter-muscular fat. Don't freak out if you cut too deep. Just stop cutting and back off. A small flap mistake is not the end of the world unless you remove it completely. (It's still not that bad).
- I've always injected my flats with strong beef broth...just because. It's cheap insurance. I've experimented with injecting tallow, but at least for me I haven't seen the benefit of adding the fat. In long cooks you'll lose that just like the "real" stuff. YMMV
- Don't be too heavy handed with rub (or binder). Rub builds bark, but if you can't see the meat at all after applying rub, the smoke can't see it either. I learned this the hard way. Exotic rubs are for later. I haven't found the need to get exotic yet on briskets. My brisket rub is 4 tbs kosher salt, 4 tbs coarse black pepper, 1 tbs garlic powder, 1 tbs onion powder, and 1 tbs of paprika. There are a million variations to rubs, but this is simple and reliable for me for beef (briskets, dino ribs, cowboy steaks, and even hamburgers).
- Don't get overly creative with messing with pit temperature. I know a lot of people like to start at 180 then later ramp up the temp. Since I do most of my long cooks overnight, the only time I want to get up is to wrap at around 160 - 165 in anticipation (or realization) of the stall. If you want more smoke, use a smoke tube. I take wood chunks and cram them into a smoke tube packed tight with pellets. I blast it with a plumbers torch to burn solidly before putting into the smoker. I rarely use a smoke tube as I know I'm going to be cooking for a long time and the smoke will accumulate over time. Nearly all of my slow cooks are 225 for the duration or at least until I've wrapped.
- Plan on an overall cook of about an hour per pound (before trimming) if cooking at a lower temp. This is totally a guide, but not a rule to follow. You always cook until probe tender.
- Again, I do long cooks overnight as these crazy contraptions still let you sleep. I set a third party temperature alarm (Thermoworks Signals) for 165 and blindly wrap in butcher paper when the alarm goes off. If I'm a little early or late for the stall, life and cooking still move forward. I do not do anything fancy with spritzing or otherwise when wrapping.
- You need to start paying attention at around 195, but in my world, I can almost always be where I want to be at 200 - 203 internal temp. I don't know who thought up 203, but it's been a magic number for me for years. Again, still test for probe tenderness.
- Give yourself at least several hours of rest. The ice chest with towels, moving blankets, etc. works great. I've let briskets sit like this for 4+ hours and they still come out hot to the touch and perfect for slicing and eating. If you're staying at home, don't have a big ice chest, etc. just preheat your oven to like 170 - 180. Overwrap the brisket, paper and all with foil. Put it in the oven and turn the oven off. It will sit happy as can be until you're ready.
- If doing a full packer, it may behoove you to look at some videos of how to slice the flat versus the point. I screwed this part up for years. The grain of the flat and the point are not in the same direction!
As I said up front, there are many ways to mess around with cooking briskets. I found a simple approach that produces predictable results without me compromising my sleep, spending a lot of time messing with my cook, etc. and most importantly worrying about the final product. After all, this is supposed to be an enjoyable experience.