Just reduce portion. If you get used to eat a lot, then reducing half can make you crazy hungry. However, human body adapts fast. If not how those people that fast can adapt, but do they reduce 5 kg during fasting months? The answer is no. The main reason is body adapts to conserve energy. Well, not because sleep during lunch hour only but human body can reduce metabolism automatically. That is why weight drops when dieting drops fast to certain degree and then slows down. It will take time.

actually nasi is the one responsible for your menggigil badan
specifically your previous nasi, make you crave more nasi mengigil for next meal
kinda like drugs sugar is

try eating breakfast with rice
see how you fast you mengigil to eat rice for tengahari

now try eat something less simple carb in the morning
see how long you can stand before next meal

sure you're still too 'addicted' to rice, it wrecked your hormone (insulin and ghrelin)
after no simple carb or no carbs in the morning for like 1 months
you'll see yourself getting accustomed with not eating rice and not mengigil anymore
that also explain how people after 1 month fasting, at end of fasting month dont care about sahur and not so hungry anymore