The chicken and basil part is honest food: 100g of minced chicken is 165 calories and the basil, chili and garlic are nearly zero. The rice is 260 for a normal 200g scoop. What pushes the plate past 600 is the fried egg, which soaks up wok oil until the edges go crispy and lands at 110 to 150 calories on its own, plus the tablespoon of oil the cook used for the stir fry.
Meat choice changes the number more than most people think. Minced chicken keeps it at 630. Swap to minced pork and it climbs to about 680 because Thai minced pork is usually 20 to 25 percent fat. Order kra pao moo krob (crispy pork belly) and you are at 820 or more, since 70g of moo krob is nearly 300 calories by itself.
This was my default 45 baht lunch for a long time and it is a perfectly good one. The trick I settled on: keep the egg, ask for less oil, and do not order the extra rice. A 630 calorie plate with 30g of protein is a full meal. A 900 calorie plate with kao piset (extra rice) and moo krob is two meals.