This is more or less the recipe we use:
6 C kosher salt
4 C white sugar
2 C brown sugar
1 C honey
1/4 C minced garlic
1/4 C pickling spices
3/4 C pink salt
4 Gallons water
This is a modified recipe from Charcuterie, btw. So you put everything in the water, bring it to a boil mixing to dissolve, then let it cool to room temperature. You will be GREATLY served by having a meat injector. If you do have one, inject your brine directly into the fatter parts of the meat. We use the flat, the lean end, of the brisket only. These are generally 7 lbs each and this recipe can fit about 4 flats comfortably. Without injection, it's very difficult to get the cure to the center of thicker slabs even with prolonged immersion and regular agitation. However, with injection you can get a good cure after 5 days in frig, turning daily. (Charcuterie says something like 3 days, which is boloney, and he recommends the plate; the extra fat makes that even tougher.)
You want to make a spice rub of ground coriander seed and pepper for the outside. I suggest making it pretty fine. Then smoke the meat at 200-250 for about 7-10 hours or until it reaches an internal temperature of about 175 degrees. Let it cool and then steam it for about 2 hours or until tender, but not falling apart tender. Two steamings often work better than one long one for some reason. btw, if you use all wood it will probably be too smokey. Try a mix of charcoal and wood.
This will give you a fairly intense pastrami, moreso than most in NY other than maybe Katz's.
Nick, aka Zuke
Do you have a smoker (or are you comfortable smoking sufficiently on your grill)? do you want to cure it yourself?
Assuming yes on both of those (you could start with the corned beef route, which certainly jumpstarts the process, but the flavoring of the cure is different than true pastrami) this is the best step-by-step process I've ever seen for doing it at home:
A few thoughts from that. First make sure you do a brisket flat. It is, in my opinion, the best cut for brisket. It's what you get at places like Katz's deli in NYC. Also, smoking it - or grilling it low on indirect with wood smoke - is really critical in getting it the right flavor.
It really isn't that hard. at all. It works great. Good luck and enjoy. It turns out superb and is light years ahead of what you get in most delis... (katz' aside)
Around St Pat time, I usually get 3 or 4 point cut corned beef briskets (I know...fatty, but it can be cut away when serving). Rub with a good spice rub, bag in plastic and cure in fridge for 3-4 days. Smoke about 6 hours in slow smoker (about 200 deg). Cool. Cover with cracked black pepper and wrap in plastic wrap, then in 2-3 layers of foil. Let age in fridge for 2-3 weeks. Depending on the brand of corned beef, you may want to soak it overnight in plain water before starting the process. It can sometimes be rather salty.