The food doesn’t have to be cooked, but there are minimum tastiness requirements and raw meat doesn’t qualify as far as I know.
Find a minion with high Marksmanship, and upgrade your camp to the point where you can send him out on hunting missions. He’ll bring back various animal corpses, which you can butcher and cook.
My current strategy is to build a blacksmith expansion and a kitchen adjacent to each other. You can use the charcoal kiln at the blacksmith yourself, so take the huge mass of splinters produced by logging missions and turn that into charcoal, then use that charcoal with the smoking racks in the kitchen (which you can also use) to turn meat into smoked meat. Smoked meat converts to camp food at 100% - I thnk it’s 360 kcalorie per chunk of meat, and it takes about an hour of your time to butcher some corpses and load a smoking rack. So with a decent hunter bringing the meat in, you can easily get ahead of the camp’s food requirements.
You can also use a trapper or foragers, but they’re not as efficient - a successful trapper will bury you in small animal corpses but they take longer to butcher for the same amount of meat. Of course, trapping is safer than hunting, so it’s a trade-off.
