Vegetables, non-berry fruits, cooked meats, cheese, and bread should be slice-able with a knife and the item in your crafting grid. Each item should return somewhere between 4-8 slices as the devs see fit. Sliced veggies and fruits could be added to cooking pot recipes as normal with reduced satiety. Sandwiches can be made at a table with 1 bread, then any 4 sliced foods or jam/honey, topped with another slice of bread.
Fried foods would be made using 1 flour, 1 egg, and 1 veggie or raw meat. The food would then be cooked in a cooking pot with animal fat at a 1:1 ratio. Fried foods would have more satiety, but only the core item would provide nutrition, making it mostly empty calories.