Another vote for fun, and changing things up. Shock your system, but don't go into starvation mode. Your body gets used to doing and eating the same thing pretty quickly, and it is easy to hit a plateau. The best thing for it, is usually to really change your food and/or your workout routine.
For food, I'd try eating about the same number of calories at first, but eat different things. If you are an ultra-low carb diet, I'd consider eating about 150-200 extra calories of carbs immediately after a long or intense ride (I prefer fruit or whole-grains like oatmeal or bulgar wheat). You want to eat no more than 10 minutes after you get off the bike. If I do this right when I get home, and then take a shower and change clothes, I tend to not eat as much over the rest of the day. If you are already eating carbs, I'd just change things up a bit. Switch out your carbs for something completely different, maybe a bit more protein and fewer carbs, more dark-colored vegetables and fruits, etc. Make most of your fats come from nuts for a couple of days. When my body gets enough of the trace nutrients found in such foods, my cravings usually go way down after a day or two.
For exercise, just do something that burns about the same number calories, but stresses your body in a different way. On the bike, add in more hills, or do fast-feet intervals. Maybe add-in semi-aerobic weight exercises like lunges with dumbbells, leg press exercises using a weight that you can do sets of 35+ reps, etc. It never hurts to throw in a few weights, abdominal, and flexibility exercises either (yoga, pilates, etc.). Some people like to switch some of their aerobic activity to something else like running, elliptical trainers, or rowing.
That is what has worked for me, and others that I know, in the past. Now, I need to follow that advice myself!