If you need to eat more or fewer calories per day, you can adjust accordingly by simply taking out or adding a bit more of the ingredients already included in a recipe. For example, adding/removing a tablespoon of olive oil or butter will add/remove about 100 calories. If you like or dislike certain recipes, feel free to shift things around. Make sure to keep an eye on the calories so you’re still falling within an acceptable range of your daily goal.
Probably the most popular option is fasting for 16 hours (including sleep), which is usually easy to do on a keto diet. It requires trading breakfast for a cup of coffee (or some other non-caloric fluid) and having lunch as the first meal of the day. Fasting from 8 pm to 12 noon – for example – equals 16 hours of fasting. Another option is to skip dinner: eat breakfast and lunch within 8 hours — for instance, 8 am to 2 pm — and then don’t eat again until 8 am the next morning.