Let me begin by saying that olive oil is awesome.
It is pretty.
It is delicious.
So people use it to cook everything and ignore all the other oils.
It is perfect for vinaigrette.
It makes lemon cake taste more delicious than butter ever could.
And it is rivaled only by butter as bread's main hang.
The thing is, you shouldn't be using it for EVERYTHING.
Compared with other vegetable oils, olive oil has a pretty low smoke point.
Smoke point = How hot something can get before it starts to smoke, burn, and eventually catch fire.
If oil gets heated above its smoke point, you shouldn't eat it, or any of the food that was cooked in it.
Because not only will it taste bad, it will also be really bad for you. When oil gets heated beyond its smoke point, it starts to break down chemically. It loses most of its antioxidants, releases toxic chemicals in the form of smoke, and becomes filled with carcinogenic free radicals. SCARY.
So as a general rule, cooking over high heat with olive oil is bad news.
And most of the stuff you cook should be done over high heat. For example, the point of searing is to get color and caramelization on the outside of a food, which can only be done over high heat. If you try to sear with olive oil, the oil will smoke before it gets hot enough to sear the food. Or, if you roast olive oil-coated vegetables at 425°F, the oil will burn in the oven. Your vegetables will be bitter and carcinogenic.
Here's when to NOT cook with olive oil:
1. When you're searing steak:
2. Or fish:
3. Or pork:
Doesn't matter if it's seared pork chops (left) or seared pork tenderloin (right) — olive oil is not your friend here.
4. Or lamb:
5. Or burgers:
6. When you're roasting chicken:
7. Or vegetables (if your oven is hotter than 400°F):
8. Anytime you're cooking in a wok:
9. Or when you're stir-frying something in a regular pan:
10. When you're deep frying anything, like chicken:
YUMMMMMMMMMMM! There is NO WAY you can do this with olive oil.