I needed a refresher in being their alpha first, friend second.
Once one or both starts growling, Cocoa will go into attack mode in 3, 2, 1... I have to get her down the quickest way I can.Scruff her neck (firmly but not to injure), then remove her from your lap. Even better, make her get down. When she growls, she's trying to establish dominance. When you scruff her and make her get down, you're telling her that you're in charge. She'll get the message pretty quickly.