Soak 4 wooden skewers a little ahead of time, if using, or use metal skewers.
Grate the onion, grate or crush the garlic and finely chop the mint and parsley (note quantity is after chopping).
Put all of the ingredients in a bowl and mix well - I'd recommend using your hands and really knead the mixture kind of squeezing it to get all the ingredients well mixed.
Divide the mixture in to four and press each quarter into a sausage shape (it doesn't have to be as long as you will want yet). Push each sausage shaped kofte on to a skewer and spread it along the skewer a bit so it thins out a little more. Put the kofte on a tray or plate and refrigerate for around 20 minutes or so to firm up a little.
Heat the grill to a medium heat and cook the kofte a few minutes each side until lightly charred and the meat is cooked through. Alternatively, you can cook them under a broiler (grill).
Video
Notes
I have made these both with and without egg - the egg makes it a little softer and lighter which has pros and cons. I recommend chilling before cooking in both cases, but especially if using egg. Overall, I would say without egg is probably more typical and what I use more often.I recommend serving with some cacik (similar to tzatziki) to cut through the richness of the meat. You can add both to a pita/wrap, along with some tomato, onion and herbs. Alternatively it works well with salads like tabbouleh and fattoush.Instead of cooking on skewers, you can also divide the mixture into smaller lengths and cook more as flattened meatballs.