520 calories for one piece of murtabak daging is honest, but to be clear, this is a ballpark estimate. Hard data on mamak murtabak is thin because every stall makes it slightly differently. The dough thickness varies, the amount of ghee on the tawa varies, and some places are more generous with the filling than others. The number here is a reasonable middle estimate, not gospel. What drives the calories is almost entirely the dough and the oil. The 100g of flour dough is around 230 calories, and the oil and ghee absorbed during frying adds another 110. The 65g of minced beef and the egg together are only 165 calories. So even if you somehow removed the meat, murtabak kosong is still 380 calories because the bread part just doesn't change much.
The thing that actually moves the number is which filling you pick. Murtabak ayam at 460 calories is the lightest meat option because minced chicken is leaner than beef or mutton. Murtabak kambing hits 560 calories because mutton has more fat. The difference between ayam and kambing is 100 calories, which sounds small but across a week of regular mamak visits it adds up, lah. The other big variable is whether you soak it in kuah dalca or curry on the side. That gravy probably adds another 50 to 100 calories depending on how much you pour. If you're watching your numbers, eat it plain, pick ayam over daging, and don't order a second piece because it doesn't feel heavy until suddenly it does.