Sometimes life dictates you need to eat junk – maybe you’re out and about and there is nothing to choose between.
Maybe you’re out with friends etc.
Maybe you just can’t face cooking another low fat stir fry.
My tips are to reduce the quantity and up the protein.
If it’s spicey food, I try to go for a kebab. Or if it’s a curry, I eat the meat and only 1/2 the rice. Or if it’s a McDonalds, try to eat it in the morning/lunchtime to give the body time to burn it off. Or adjust your calories south for the rest of the day.
When I go for tapas, I load up on calamaris and meat dishes, with a few bits of bread. The protein is less likely to be stored as fat but also reduces your appetite.
If it’s pizza, I try to eat a small one or 1/2 a 12″.
Quantity is soooooo important. I’ve seen many people eat bad food but no gain weight because they expend more calories than they injest. You might see your grease monkey mechanic eat a sausage roll, but it might be the only thing he eats for most of the day.