350 calories for a bowl of bubur lambuk is honestly pretty reasonable for a full one-dish meal, bro. The rice base is only 150 calories because it's been cooked down into porridge with a ton of water, so you're getting a lot of volume for not that many carbs. The calories actually come mostly from the coconut milk (60 calories in just 40ml) and the cooking oil or ghee with the aromatics (55 calories worth). The meat at 65 calories is the most useful part nutritionally, giving you 18g protein which is solid for a porridge. Fair warning though: hard data on bubur lambuk is thin, so treat this as a ballpark estimate. The mosque recipe varies every year depending on who's cooking, and the quantities of santan and ghee are not exactly standardized.
What really changes the maths is how heavy-handed the cook is with the santan and ghee. The mosque version at 350 calories uses moderate coconut milk. A restaurant version with full santan and generous ghee jumps to around 430 calories, same bowl size, just creamier. On the lighter end, the vegan version with minimal coconut milk and no meat drops to about 220 calories, which is genuinely low for a filling bowl of porridge. If you're collecting your free bubur at the masjid during Ramadan and you want to keep it sensible, the portion size matters too. A smaller bowl at 250g is probably closer to 250 calories. The gravy at the bottom of the container is where most of the fat hides, so if you're watching it, go easy on ladling that last bit out.