Patiently and carefully like any other employee but more so! They would need to have a good pallet. Equally important, to me, they would have a demonstrated desire and passion for roasting coffee already. Demonstrated by already roasting coffee and exploring profiling on their own. I've been asked by numerous people the past few years customers, employees and baristas from other shops, if they could apprentice with me to learn to roast coffee. My answer is always the same: if you really wanted to learn to roast coffee you would have already and can. Hit the internet starting with Sweet Maria's website and start by home roasting. Only ONE person has done so, an at the time customer. Most people are looking for easy short cuts. I don't want them. Today that customer is our assistant manager of our main coffeehouse.
Great post, per usual, Mike.
In 2 weeks, I'll be starting to train my first apprentice. He is what Mike described. Great palate (leads our staff cuppings every week), home roasts, and wants to be career coffee (and better yet career thirty-thirty). He has designs to start barista competitions down the line. We have decided the best plan is to not rush competition. We all know barista competitions are all about knowing as much as possible about brewing fantastic coffee. I'm convinced truly grasping coffee begins by learning the process in a hands on manner from seed to cup. This will be a step further back in the chain for him, and I think it's an important, foundational step. Tony Acord. Remember that name and watch out!
I guess to sum it up, have someone who's passionate, has a great work ethic, a good palate, and wants to be with you for some time. Training a roaster is very very expensive. Pick one who will care for the coffee and wants to make it worth your company's time and expense by being consistent and sticking around.
By the way, Sarah, you're absolutely right. Letting go of that kind of control is terrifying. Make sure you get the right person, or trim the fat as soon as you can if it's not working out.