The major difference is that the pressure cooker/slow cooker limits evaporation. While traditional cooking methods evaporate excess liquid, a pressure cooker/slow cooker cooks in a sealed pot. If you’re adapting a standard recipe, it’s best to reduce the liquid by roughly ⅓. Even though you reduce the liquid, you might be surprised the cooking liquid hasn’t changed much or might be increased after all the ingredients release their juices! Keep in mind that you might need to further reduce the liquid after pressure cooking/slow cooking. Add the ingredients into the pressure cooker/slow cooker the exact way your regular recipe calls for, keeping the amounts of seasoning or oil the same. As for cooking time, I highly recommend checking the instruction manual of your gadget for proper cooking time. If necessary, you will need to pressure cook/slow cook in batches.