This will not be a cookbook that teaches people how to make/use cannabutter. It will simply be a cookbook, filled with relatively easy and simple, yet delicious recipes,...
If I can offer any advice, since I have no plans to write a cookbook myself, go with the cheap and plentiful angle; Do not refer to it as a stoner cookbook or anything of the sort because you will alienate medical users(This would market to the 14-20yr old crowd, they can barely read let alone buy a book), try to focus on either extremely easy or very high leftover value (IE: Pop it in the oven or microwave and tastes fresh).
People saying to start a blog bring up a point which is online exposure, in this area your steps are simple; Internet exposure is all about mass marketing, every single social media outlet should have a page dedicated to your book,(I know many artists who could design a concept book cover for visual appeal), as well as your own website that will serve as a contact hub for you as well as a place to link to for current news; Don't know html xml java or any of that? No problem, tons of free templates out there, most hosting providers will also provide you with basic tools or design it for you, this is where you can put your 'blog'.
People want things that are new, a blog in terms of just writing something new or your thoughts provide that and keep your presence from being forgotten. You can also include a 'recipe of the week/month' as a sample of what you provide with the full book. Finally, pictures, pictures, and more pictures; Of literally anything, they just need to be new, throw on a MJ leaf apron and make a photo journal of 'Tonight's Dish',(Pictures of everything that went into the finished product and every step along the way), the more pictures the better, you will want them when editing.
Good luck, don't let anyone discourage you, and if it is a professional looking book, not something I might find under my nephew's bed, I would buy it.