So I said I was making "pastrami a la Extramsg." It's true that his recipe is already available here. It's also true that it's for 6 or 7 briskets, not one. And as a consequence, I usually divide by 6 to 7 in my head, which is to say, I wing it a bit with his old post as a guideline. So it wouldn't be a bad thing to post my own rough recipe for a single pastrami, adapted from Extramsg's guidelines as well as from the recipe in Ruhlman's Charcuterie.
Okay, for starters, there are five special things you need:
1) Whole raw brisket, point and flat, if possible (and if you like the extra-fatty point meat as well as the leaner flat meat). There are various guidelines here on LTH about where to get a good whole brisket; I go to Excel Corned Beef. Obviously you want one that hasn't already been shot full of chemicals.
2) I assume you have a WSM, or some other smoker.
3) You need something big enough that you can brine a whole brisket in it in the fridge. A stockpot or food grade bucket can work, I went to a restaurant supply place and bought a food grade bin big enough for this kind of thing, about $20.
4) Pink salt, curing powder, Prague Powder No. 1, whatever you want to call it. Available at soon-to-be-GNR Spice House, Paulina Meat Market, etc. While you're there, pick up pickling spices.
5) A Cajun injector, that is, a big hypodermic for squirting brine into the middle of meat. Not absolutely necessary, you can just poke it full of holes and that will help it soak up the brine.
Assuming your brisket is in the 12-14 lb. range, adjust if substantially larger or smaller:
Put 2 gallons of water in stockpot. Add:
1-1/6 cups kosher salt (yes, I know your cup measure doesn't show sixths, wing it)
3 tablespoons pink salt
3/4 cup white sugar
1/3 cup brown sugar
2 tablespoons honey
1-1/2 tablespoons pickling spice
1 tablespoon whole coriander seed
1 tablespoon whole mustard seed
3 or 4 cloves garlic, minced
Heat the above, stirring, enough to dissolve the salt/sugar. Let cool completely; you don't want to put meat in hot liquid. Trim the biggest, thickest hunks of fat off the outside of the brisket; you want some fat cap but there's no real reason to cure an inch of thick white fat.
Put the brisket in the brine in your vessel. Poke it with the injector and squirt brine into its insides liberally, especially in the denser middle of the flat. Note that it will often squirt back out. This will be annoying if it hits the floor and painful if it hits your eye. Weigh it down with a plate, whatever, to get as much submerged as possible.
Stick in fridge for a week or so. Turn once if needed. Otherwise leave the hell alone.
* * *
A week later, build a fire in your WSM according to the principles in your autographed copy of Low & Slow. You're basically going to do a brisket cook, which is basically like a pulled pork cook (p. 175), except for two things: one, you test how a brisket is done differently, and two, a cured brisket will probably cook faster. (For instance, at the picnic, my cured brisket was done in about 7-1/2 hours, Steve Z's regular one, admittedly larger to begin with, took 13.)
For the outside rub, lightly toast in a frying pan about 3 TBSP each of black pepper and coriander seed, then grind in a coffee grinder. (It's pungent, so before you grind coffee in it again, clean it well and then grind some uncooked rice.) Spread this all over the outside.
Cook for 2-1/2 hours on one side, 2-1/2 on the other, repeat, and somewhere around 7 or 8 hours, you should be able to stick a fork in it and wiggle it around even in that densest portion of the flat. That, for me, is the best sign of when a pastrami is done.
You could eat it now. It would be very good, maybe a little tougher than typical deli pastrami but tasting wonderfully of the fresh smoke. Or you could refrigerate it and then, the next day, cut it in half or a third or something and steam that piece in a steaming insert in a stockpot for about 2-3 hours, until it's back to an even wigglier fork-in-the-middle texture. (The extra freezes fine, I think, since it'll be steamed again anyway.) Now it's really done up right. Carve it so your sandwiches will include both the fatty point and the leaner flat, and maybe some of the burnt ends too which will be very smoky, salty and peppery. Serve with great bread and brown mustard. Enjoy.

photo by Gleam