We got some delivery and one of the dishes is just Terrible. It's inedible. Three people tried it, three people gagged. It's mac&cheese that tastes like they left the cheese in the bottom of the wet fridge for a month, and maybe a hint of soapy flavor to it too. We've gotten this dish before and it was good, so I don't think it's just that the chef has a disgusting palette.

Would you take the food back to the restaurant for a replacement dish, or is that an American thing?

It's a bit of effort with a delivery but you should at least call them up, maybe send them a picture and see if they'll give you credit or something? It's not just an American thing, if something you paid for is shit you should complain. I wouldn't complain as much in Khmer restaurants as they like bones and sinews and stuff I don't. I got a quite good salad in a nicer local place a while back. When I asked for some dressing they gave me a bowl of ketchup. I complained so they gave me some ketchup mixed with that fake mayonnaise. I gave up then.

I once ordered a fruit salad for breakfast and it came with a nice topping that looked like yoghurt. First bite and I found out it was that horrible white mayo-whatever cream. When I complained the waiter said: "Fruit salad same salad have majonese". I gave up and ordered toast and 2 fried eggs. I paid for the fruit salad too. Never went back since.