They are basically meatballs of ground beef you smash down. My main issue is get enough equal force to make the ball equally flat. The flat spatula does sound like it would work though. Thanks.
Energy bars sound like a good fit. I take a brand on hikes called Luchos Dillitos and they are good for quick energy boosts and are based around guava so are relatively healthy. For a non-special purchase option, a popular option to get that protein/carb mix is something like a trail mix, nuts...