Plastic chairs, plastic tables, often of seemingly dubious cleanliness, on the pavement or in the gutter.
A stall that sells one thing and one thing only and has been doing it for two or three generations (move fast - the latest generation don't want to work so hard so these businesses will expire with their current operators)
Old family coffee shops, often without a menu - just point at what someone else is eating and say "la". Try kaya toast and a half-boiled egg for breakfast: it meets the Malaysian objective of "cheap and good." Don't be squeamish about the egg. They usually make coffee to put the chains to shame for MYR1 and a bit.
One of the handful of family owned restaurants that have been around for 40 or 50 odd years. Some are big, some are small.
Local food in upmarket hotels. It's sanitised, internationalised and prettied up to the point where its anodyne.
Tea in even mid-range hotels. Last week I was charged MYR20 for one cup of tea. Today at a stall, I had chicken curry, squid in sambal, mixed veg and rice for MYR10.
Anything with a Chef's name over the door: it's almost always going to be farcically overpriced and often not very good, service so offhand that you'd think you'd been magically transported to a snooty Parisian restaurant and, worst of all, a drinks menu that makes the food look really, really cheap.
Some want to kill the street food culture in KL, or to move it into "food courts." SIN has done that and, with no choice, people use them. There are some food courts in KL shopping centres. Some are busy when it rains. Others are more or less deserted.
Street food belongs in the street - and when it's proper grown up meals served in the street, so much the better.